The Metis Files Series by Brian S. Leon

Eternal life. Eternal battle. Steve—Diomedes Tydides to his Trojan War buddies—just had a bad day on his charter fishing boat in San Diego, but when the goddess Athena calls on her faithful warrior for another secret mission, he’s ready. The bomb that exploded inside the Metropolitan Museum of Art isn’t the crime American authorities think it is. Someone also stole the Cup of Jamshid, and Diomedes knows its fortune-telling abilities won’t be used for anything benign... moreEternal life. Eternal battle. Steve—Diomedes Tydides to his Trojan War buddies—just had a bad day on his charter fishing boat in San Diego, but when the goddess Athena calls on her faithful warrior for another secret mission, he’s ready. The bomb that exploded inside the Metropolitan Museum of Art isn’t the crime American authorities think it is. Someone also stole the Cup of Jamshid, and Diomedes knows its fortune-telling abilities won’t be used for anything benign. Though Diomedes recovers the Cup from a determined shaman holed up beneath Central Park, when he finds his allies slain and the Cup taken once more, he knows he’s up against a truly powerful enemy. Over a millennium has passed since Diomedes last contended with Medea of Colchis, deranged wife of Jason the Argonaut, but neither her madness nor her devotion to Hecate, goddess of witchcraft, has waned, and she intends to use the Cup of Jamshid to release across the world a dark brand of chaos unseen in human history. Immortal since the Trojan War, Diomedes must once again fight for mortals he understands less and less, against a divine evil he may never truly defeat. less

Framed for the murder of a high ranking member of the Unseelie Court of Fae, Steve Dore–also known as Diomedes, Guardian and protector of mankind–goes on the run. He’s determined to uncover the real culprit and clear his name.But the assassination may be the beginning of a more sinister plot that involves not just the Fae and Humankind, but all the races of the world. And what if the real assassin is a boogeyman even the Fae don't believe is real?

Millennia ago, beings we call angels were tasked with watching over humankind in its infancy. Rather than protect humans, these Watchers decided to subjugate them instead, beginning a rebellion that would rock both Heaven and Earth. Defeated, the most powerful of the Watchers were imprisoned for eternity, while the weaker ones were condemned to live out their existence on Earth, relegated to the shadows that now occupy human myths and legends. Until one of the Watchers escapes... moreMillennia ago, beings we call angels were tasked with watching over humankind in its infancy. Rather than protect humans, these Watchers decided to subjugate them instead, beginning a rebellion that would rock both Heaven and Earth. Defeated, the most powerful of the Watchers were imprisoned for eternity, while the weaker ones were condemned to live out their existence on Earth, relegated to the shadows that now occupy human myths and legends. Until one of the Watchers escapes. Immortal protector of humanity and one-time hero of the Trojan War, Diomedes—better known as Steve Dore these days—is horrified to discover that what human authorities think is a mentally unstable cannibalistic murderer is actually a gateway to something ancient and apocalyptic. Racing against a cosmic timetable, Diomedes is drawn into a dark and sinister underworld in a desperate attempt to stop another uprising. But stopping this enemy may cost him far more than his life. Some grudges never die. less