Books like 'The Enemy Within'

Readers who enjoyed The Enemy Within by Patty Jansen also liked the following books featuring the same tropes, story themes, relationship dynamics and character types.

sc-fi space military, war & conflict space-opera soldiers exploration space-travel space-fleet aliens invasion

No Retreat by J.N. Chaney, Terry Mixon
Rated: 4.50 of 5 stars
· 12 ratings
When things are going to plan, check to see what you’re missing.Admiral Jack Romanoff and his crew are trapped inside the Confederation proper and facing an unknown number of alien attack ships. They’d thought the Tardan military was defeated, but they’d been wrong. Now they were trapped in a fight they couldn’t lose.When everything seems exactly as you’d hoped, figure out what you’ve missed...

Categorized as:
space-opera military first-contact aliens invasion soldiers space-travel exploration
Under Siege by J.N. Chaney, Terry Mixon
Rated: 4.50 of 5 stars
· 12 ratings
Only one world in the cluster remains in enemy hands.Admiral Jack Romanoff and his crew have one remaining nut to crack before they can turn their attention to the people that overthrew the Confederation. The Vesuvius system has become a fortress, so it won’t be an easy fight, but it is one they cannot lose and survive.When force alone won’t do the trick, add guile...

Categorized as:
military space-opera first-contact aliens invasion soldiers space-travel exploration
Operation Liberty by J.N. Chaney, Terry Mixon
Rated: 4.50 of 5 stars
· 12 ratings
Aliens invaders hold human worlds. That cannot stand.Admiral Jack Romanoff and his crew have defeated the Locusts once and for all, but they are far from the only invaders infesting the Confederation. The time to go after the xenophobic Novarites and free those worlds has come, and nothing will stand in his way.If words aren’t enough, show them your teeth and bite deep...

Categorized as:
military space-opera first-contact aliens invasion soldiers space-travel exploration
Empire by Joshua Dalzelle
Rated: 4.63 of 5 stars
· 8 ratings
The final fight for control of humanity begins now.The United Terran Federation is on the brink of collapse after a devastating attack by the Eastern Star Alliance that has left four planets depopulated and uninhabitable. Terrified member worlds are fleeing from the Federation and the remnant of their once-mighty fleet has retreated to the last place they are welcome: Earth...

Categorized as:
colonization first-contact military soldiers space-fleet space-opera adult book
Destroyer: A Military Space Opera by Craig Martelle, Michael Anderle
Rated: 4.63 of 5 stars
· 8 ratings
Humanity’s greatest export—Justice. Peace can never last.When things are going right, be very afraid. The laws of chance are coming.And they’re bringing an alien destroyer, invisible to systems, sensors, as well as the naked eye. Even Ted is stymied. Kill or be killed.Terry Henry Walton isn’t afraid to do things the hard way, and he shows everyone what that means...

Categorized as:
space-opera exploration first-contact space-fleet military space-travel soldiers sci-fi
Ice World by B.V. Larson
Rated: 4.55 of 5 stars
· 20 ratings
Long before Earth began conquering her neighboring stars, Legion Varus was deployed on Tau Ceti. Valuable and highly illegal treasures were stolen during the campaign, but McGill never gave it a second thought.The Tau haven’t forgotten him, however. For decades they’ve hunted and plotted, and at last they’ve found the pirate who robbed them. Tau agents invade Earth seeking revenge and profit...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
The Colossus by Jay Allan
Rated: 4.50 of 5 stars
· 10 ratings
The Hegemony strikes again… The Confederation and its allies have won their first victory, retaken their capital from he forces of the Hegemony. But the enemy is not beaten, far from it, and they are back, with an unstoppable weapon, a vast superbattleship, a deadly hybrid of imperial and Hegemony technology, called the Colossus...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Fires of Oblivion by Anthony James
Rated: 4.50 of 5 stars
· 10 ratings
Captain John Duggan rots in his cell, facing execution at the hands of his captors. Having discovered the secret which the Ghasts wished to remain hidden, he is left powerless to find answers to the questions which will determine the future of the Confederation. Elsewhere in the Garon sector, the Dreamers have been putting their own terrible plans into action...

Categorized as:
aliens exploration military soldiers space-fleet space-opera space-travel adult
The Forever War by Raymond L. Weil
Rated: 4.50 of 5 stars
· 10 ratings
From USA Today Best Selling Author Raymond L. Weil comes the fourth book in the Star Cross series. The Vorn have returned with a massive fleet and are once more harvesting the intelligent worlds of the galaxy for food. Every fleet placed in front of them has been annihilated by the Vorn’s superior weapons. The Vorn seem unstoppable as they harvest world after world...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Galaxy in Peril by Raymond L. Weil
Rated: 4.50 of 5 stars
· 10 ratings
he situation in the galaxy is growing desperate. Every day the Vorn are harvesting world after world to be used as food for their Queens. The Vorn ships are nearly indestructible and destroying every fleet that dares to oppose them.Lakiam Fleet Commodore Dreen is trying to form an alliance to try to stop the Vorn, but he needs a victory to bring other Protector Worlds to his side...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Nua'll by S.H. Jucha
Rated: 4.42 of 5 stars
· 12 ratings
The Omnian expeditionary fleet sails for the faraway place they call “the wall.” The worlds of humankind have consolidated their resources to create a powerful armada to confront the alien federation.During the Omnians’ previous encounter with an alien fleet at the wall, the Nua’ll comm sphere spoke to them in multiple languages...

Categorized as:
aliens exploration first-contact invasion military space-fleet space-opera space-travel
The Lost Supernova by Vaughn Heppner
Rated: 4.42 of 5 stars
· 12 ratings
Androids used to mingle among us, pretending to be human. Then an alien puppet-master altered their programming. Unknown to us, androids began leaving human society, burning their clothes and peeling off their skin to reveal the chrome-colored bodies underneath. They gathered in a system were a star had exploded, blowing away the atmosphere of a Jupiter-like planet...

Categorized as:
aliens colonization exploration invasion military soldiers space-fleet space-opera
Earth Ascendant by Raymond L. Weil
Rated: 4.42 of 5 stars
· 12 ratings
From USA Today Bestselling Author Raymond L. Weil comes the second book in a new military science fiction series.The war between the seven alien races of the Confederation and Earth heats up as the two come into direct conflict over the former Human Empire. The people or Earth are determined to free it, and the Confederation is determined to keep it under their strict control...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Artifice by S.H. Jucha
Rated: 4.42 of 5 stars
· 12 ratings
The great spheres and probes of Artifice, humankind’s enemy, haunt every inhabited world near and far. The Omnians’ long and arduous search for Artifice has ended. They’ve located Artifice’s lair in the Talus system. The sentient digital entity rules a vast swath of worlds, known as the federacy, through ruthless intimidation...

Categorized as:
aliens exploration first-contact invasion military space-fleet space-opera space-travel
Empire's Gambit by D.J. Holmes
Rated: 4.67 of 5 stars
· 6 ratings
The Karacknid assault on Earth has been turned back at great cost to both sides. Only the intervention of the Kulreans saved Humanity’s homeworld from certain destruction. Yet the Kulrean worldships cannot be used for offensive operations. This means Humanity and her allies have only a few months of respite before the Karacknids can make good their losses...

Categorized as:
colonization exploration military soldiers space-fleet space-opera space-travel adult
Nemesis of Mars by Glynn Stewart
Rated: 4.67 of 5 stars
· 6 ratings
A failed attempt on the Mage-QueenAn old friend from the gutterAn enemy that should be dead...When a kidnapping attempt on the Mage-Queen of Mars is thwarted by luck, leaving thousands dead in its wake, Prince-Chancellor Damien Montgomery returns to field operations one more time. The evidence leads to one place: Tau Ceti...

Categorized as:
aliens exploration invasion military soldiers space-fleet space-opera space-travel
Leviathan's Fear: A Military Sci-Fi Series by Craig Martelle
Rated: 4.67 of 5 stars
· 6 ratings
Trapped in Ga’ee space, Leviathan runs for its life.And the lives of its crew.Declan Payne and Harry Wesson decide to go on the offensive. They have no choice.They can’t go home. It only delays the inevitable.The Ga’ee march relentlessly into the space of the seven races while turning an inward eye toward the interloper, the ship they call God1...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Overwhelming Force by Craig Martelle, Michael Anderle
Rated: 4.67 of 5 stars
· 6 ratings
The keys to the universe……are hidden on two different planets, both at war. The Bad Company is the only force capable of unlocking destiny.Terry and Char take the Bad Company beyond the frontier, back to Benitus Seven. What they find shocks them to the very core of their beings.Marcie and Kae develop a new force, a land army to win the peace and keep it...

Categorized as:
exploration first-contact space-fleet military space-opera space-travel soldiers sci-fi
Give No Quarter by Jamie McFarlane
Rated: 4.46 of 5 stars
· 21 ratings
Alternate cover for ASIN B01FQ57I7G can be found here: Give No Quarter Branded criminals and on the run from the most powerful corporation in the known universe, Liam Hoffen and the crew of Hotspur have a simple choice to make...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Raven's Flag by Glynn Stewart
Rated: 4.57 of 5 stars
· 7 ratings
In times of peace, alliances wither and are forgotten.In times of war, honor must reforge them in fire and steel!The United Planets Alliance fought the Kenmiri Empire with a hundred allies at their side. Bound in common cause until genocide broke the Kenmiri—and Kenmiri schemes broke the alliance in turn—those one-time allies still left deep debts of blood and friendship behind...

Categorized as:
military aliens exploration space-opera invasion soldiers colonization space-fleet
Guns of the Valpian by Anthony James
Rated: 4.50 of 5 stars
· 8 ratings
Captain John Duggan and his crew are stranded deep in hostile terrritory. Their spaceship, the ESS Crimson is damaged beyond repair. Enemy warships hunt them, eager to locate the vessel which has caused so much damage to their military. All seems lost. Duggan is not a man to go down without a fight...

Categorized as:
exploration military soldiers space-fleet space-opera space-travel adult book
Explorations by Raymond L. Weil
Rated: 4.50 of 5 stars
· 8 ratings
Disaster has struck the Human Federation of Worlds. The Eternals have finally found Earth and are preparing to destroy it and the rest of the Federation. They begin gathering a massive fleet to overwhelm and destroy all of the Human worlds...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Prince Peacemaker by Fred Huges
Rated: 4.50 of 5 stars
· 8 ratings
Hazard survived the war… but can he survive the peace?The empire defeated the Swarm at the Battle of Iris, but it came at a great cost. To win, Hazard King needed to reveal he was Crown Prince Henry and take command of the Imperial Fleet as War Leader. Now their enemy is suing for peace, something many in the empire don’t want to give...

Categorized as:
military aliens invasion colonization space-travel soldiers first-contact space-fleet
Prince Commander by Fred Hughes
Rated: 4.50 of 5 stars
· 8 ratings
Hazard King was ready to get back to a normal life…Well, as normal a life as the next emperor of the Brittania Empire could expect, anyway. Hazard wanted to continue his naval career—to grow and take on positions of higher responsibility—because he knew the Swarm would be back, and he intended to be there to fight them when they returned...

Categorized as:
aliens invasion colonization military space-travel soldiers first-contact space-fleet
Federation Marine: Recruit by Jonathan P. Brazee, Jonathan P. Brazee
Rated: 4.50 of 5 stars
· 8 ratings
Previously published as “United Federation Marine Corps”, now updated and re-edited. What would you do to change your life? How far would you go? How hard would you fight?Rather than work his bones into dust toiling away on a barren world, Ryck Lysander chooses to enlist in the Federation Marine Corps.But as he quickly finds out, this path isn't just a job. . . it's a calling. .

Categorized as:
military aliens invasion colonization soldiers first-contact space-fleet sci-fi
Discovery by Craig Martelle, Michael Anderle
Rated: 4.50 of 5 stars
· 8 ratings
The hero the universe needed and her friends.People who embrace justice as much as she does. Her people. One team, holding villainy at bay, even if they are demons from the past come back to haunt them all.A Queen. Two colonels. A contract that's too easy. A vacation gone awry. Enemies and allies.Terry and Char find themselves trapped.Here comes Bethany Anne. Here comes the Bad Company...

Categorized as:
exploration first-contact space-fleet military space-opera space-travel soldiers sci-fi
Liberation: Age of Expansion - A Kurtherian Gambit Series by Craig Martelle, Michael Anderle
Rated: 4.50 of 5 stars
· 8 ratings
Humanity’s greatest export—Justice. Space is a dangerous place even for the wary, and especially for the unprepared. The aliens have no idea. Here comes the Bad Company. When humanity is wronged by the alien AI, the Bad Company leaps to action, but only after the warriors have scattered to the four corners of the galaxy...

Categorized as:
aliens space-opera exploration first-contact space-fleet military space-travel soldiers
Junkyard Veterans by Jamie McFarlane
Rated: 4.53 of 5 stars
· 17 ratings
With a price on their heads, grumpy old vets will risk everything to bring alien assassins to justice.Someone is killing off the old team of vets who repelled Earth’s first Korgul invasion. With the end of a war precious few even knew was happening, life’s been peaceful...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-opera
Galactar by Anthony James
Rated: 4.40 of 5 stars
· 10 ratings
Following decades of war and the recent catastrophic loss of an entire planet, the Human Planetary Alliance is riven by internal disputes and rivalries. The military’s old guard fights for power against those who see a chance to turn things around.After a series of hard-fought victories, Captain Carl Recker is becoming recognized as a man who gets results - a man who knows how to beat the Daklan...

Categorized as:
aliens exploration invasion military soldiers space-fleet space-opera space-travel
Oblivion's Light by Raymond L. Weil
Rated: 4.40 of 5 stars
· 10 ratings
Two more years have passed for the Lost Fleets trapped in the Triangulum Galaxy. It’s becoming more apparent with each passing day that the Dyson Sphere of the Simulins must be destroyed if Fleet Admiral Jeremy Strong and his people want to survive. Rear Admiral Kathryn Barnes sets out on a mission of discovery seeking allies against the Simulins...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Genesis by Raymond L. Weil
Rated: 4.40 of 5 stars
· 10 ratings
Fleet Admiral Jeremy Strong is determined to preserve the planet Gaia as the new home of the lost fleets. Unfortunately, a new and frightening danger from the destroyed Dyson Sphere threatens to undo everything he has fought for. Kazak, the AI on the Originator ship has his own agenda. The Humans and Altons will either do as he demands or he will destroy them...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Fulcrum Gun by Anthony James
Rated: 4.40 of 5 stars
· 10 ratings
Lost in hostile space and pursued by the most powerful warship in the known universe, Captain Carl Recker is losing hope and running out of options. His battleship Fulcrum is no match for this enemy and the Meklon aliens who might have helped him are dead, killed by the Galactar’s murderous weaponry.Somehow, Recker must find a way to succeed where the might of an alien empire already failed...

Categorized as:
aliens exploration invasion military soldiers space-fleet space-opera space-travel
Universe in Danger by Raymond L. Weil
Rated: 4.40 of 5 stars
· 10 ratings
The Lost Fleets have settled on an Originator Dyson Sphere in preparation for their greatest test yet. A great enemy is spreading across the universe conquering galaxy after galaxy.The few surviving Originators have asked Fleet Admiral Jeremy Strong to fight a war against their most hated enemy, the Anti-Life. If he fails to stop their advance, then the entire universe could be in danger...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Laws of Ancidium by Anthony James
Rated: 4.40 of 5 stars
· 10 ratings
Having fought his hardest battle, Captain Carl Recker returns to planet Lustre, bringing the alien battleship Fulcrum with him.Recker is under no illusions that he’ll be offered backdated shore leave, but his feet don’t even touch the ground before trouble shows up. A heavily armed fifty-thousand-metre Meklon interstellar drops out of lightspeed near the planet...

Categorized as:
aliens exploration invasion military soldiers space-fleet space-opera space-travel
Search for the Lost by Raymond L. Weil
Rated: 4.40 of 5 stars
· 10 ratings
From USA Today Best Selling Author Raymond L. Weil comes the second book in the Originator Wars series. The Eternals have decided to conquer Originator space. All that stands between them are the Originator AIs and the Humans, or at least that is what the Eternals believe. In preparation for the invasion, they begin gathering their massive warfleet...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
The Dark Invaders by Raymond L. Weil
Rated: 4.40 of 5 stars
· 10 ratings
From USA Today Best Selling Author Raymond L. Weil comes the second book in the Star Cross series. Over fourteen months have passed since Fleet Admiral Kurt Vickers drove the Profiteers from Earth. Eighty million people died while the planet was being ransacked and its wealth stolen. Now a new and deadlier threat comes from intergalactic space...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Shell Game by J.N. Chaney, Terry Mixon
Rated: 4.40 of 5 stars
· 10 ratings
If you can't hide the game, conceal the pieces. Admiral Jack Romanoff and his people have located the system the Tardans are using as their command post for the invasion of the Confederation. Only they can't simply attack militarily because of the stellar terrain, so they need to improvise. When the stakes are high, leave no option unexplored...

Categorized as:
space-opera military first-contact aliens invasion soldiers space-travel exploration
Lightning Strike by J.N. Chaney, Terry Mixon
Rated: 4.40 of 5 stars
· 10 ratings
In combat, speed is life.Admiral Jack Romanoff and his people have seized control of Faust and now have a base of operations, though the people of that world aren't completely pleased by his presence or actions. That's okay because he doesn't have time to worry about them. He needs to strike the Locusts before they spread even more than they already have in the wreck everything humanity has built...

Categorized as:
space-opera military first-contact aliens invasion soldiers space-travel exploration
Dark World by B.V. Larson
Rated: 4.35 of 5 stars
· 27 ratings
Two expanding interstellar powers are about to meet in battle. After the collapse of the Cephalopod Kingdom, Humanity claimed the three hundred rebellious worlds they left behind. But many light years away on the far side of disputed region, a rival power has begun to move. They're stealing our planets, one at a time...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Into the War by James Rosone
Rated: 4.44 of 5 stars
· 20 ratings
Humanity stumbles into a galactic war……a war of survival, a conflict with no endEarth has united under the banner of the Republic. Humanities brightest minds have deciphered the secrets to the alien technology and begin to reverse engineer it. An elder race takes notice of humanities strides and intervenes...

Categorized as:
aliens colonization first-contact invasion military soldiers space-fleet space-opera
Vigilance by Ken Lozito
Rated: 4.33 of 5 stars
· 12 ratings
They’ve spent years exploring this world, but they were living on borrowed time. Only they didn’t know it. Six months ago, Connor learned what the alien race that populated New Earth feared—a mysterious enemy who nearly brought about the collapse of an entire civilization. To help the colony prepare for this new threat, Connor rejoins the Colonial Defense Force...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Fracture by Ken Lozito, Scott Aiello
Rated: 4.33 of 5 stars
· 12 ratings
Colonel Sean Quinn is stranded in another universe, along with two thousand people under his command. They've been hiding from the enemy long enough, now it’s time to return home. Outnumbered against a superior foe, Sean must risk everything in a daring operation, but the mysterious enemy has a few surprises of their own...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
The Prince Awakens by Fred Hughes
Rated: 4.33 of 5 stars
· 12 ratings
Hazard King had always wanted to be an Imperial Fleet officer, just like his father.But he’s a Prince of the Realm, which make things a bit more… complicated. And when Hazard’s parents tell him that they don’t trust his older brother and want Hazard to be the Crown Prince—the heir to the throne—things go from bad to worse.And just when they can’t get any worse, the Empress is attacked...

Categorized as:
space-opera military aliens invasion colonization space-travel soldiers first-contact
Direct Fire by Rick Partlow
Rated: 4.41 of 5 stars
· 21 ratings
From street criminal to war hero.From outcast to Marine officer.The journey has been a long one, but now it’s reaching the end.Cam Alvarez leads his platoon of Drop-Troopers into the Tahni Imperium, into the final days of the war and the bloodiest battles yet...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Emergence by Ken Lozito, Scott Aiello
Rated: 4.29 of 5 stars
· 14 ratings
As the colony grapples with the realization that New Earth is not as uninhabited as they’d once thought, tensions between the colonial settlements rise to new heights, and the Colonial Defense Force finds itself caught in the middle. When Connor uncovers evidence of a militant colonial faction secretly exploiting the NEIIS, he has to investigate...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-opera
Into the Battle by James Rosone
Rated: 4.35 of 5 stars
· 24 ratings
Mankind has awakened a monster……Humanity must put aside its own animosities……or face extinctionThe origins of human history begin to unravel as Earth learns they are not the only humans in the galaxy. The sudden discovery of humans living on multiple planets beyond Earth has created more questions than it’s answered...

Categorized as:
aliens first-contact invasion military soldiers space-fleet space-opera adult
The Others by Jay Allan
Rated: 4.46 of 5 stars
· 17 ratings
From the deepest darks of unknown space, evil comes… Admiral Tyler Barron and the Confederation navy face a new threat, darker and deadlier than any that have come before...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Storm World by B.V. Larson
Rated: 4.35 of 5 stars
· 23 ratings
James McGill is sent to the Core Worlds! In an unprecedented first, Earth sends a message to Mogwa Prime. Unfortunately, the messenger is not met with enthusiasm. Misunderstandings soon threaten all of Humanity. Forced to prove Earth can serve the Empire better than any rival, McGill does his best...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
When the Axe Falls by Jon R. Osborne
Rated: 4.50 of 5 stars
· 6 ratings
The clouds of war continue to build…and not everyone is blind… Bjorn Tovesson III, the owner of Bjorn’s Berserkers, is a man tied to the past, but who’s not afraid to innovate. Whether it is new tactics or new equipment, Bjorn is willing to try anything, once, in an effort to grow his company into the status of the fabled Four Horsemen...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet
Dirty Deeds by Mark Wandrey
Rated: 4.50 of 5 stars
· 6 ratings
Old mercs don't die, you do. Abraham Murdock left his home of Sheridan Arkansas at seventeen to start a merc career that spanned almost 50 years, working for dozens of companies, killing aliens and getting paid across the galaxy. Near the end of his career, he landed a gig with Cartwright’s Cavaliers...

Categorized as:
aliens colonization exploration first-contact invasion military soldiers space-fleet

Fantastic book recommendations by book lovers for book lovers.
Find out more about thebooknaut.com.

Or - use our amazing romance book finder to get recommendations based on your favorite content tropes and themes. Mix and match at will.

© Copyright 2015-2023, Elektrolabs Limited · Advertising Disclosure: Please note that many links to retailers are affiliate links, which yields a commission for us. As an Amazon Associate thebooknaut.com earns from qualifying purchases.