Les enfants d'ailleurs Series by Nykko, Corentin Jaffré, Bannister

It's bad enough when Max, Rebecca, Noah, and Theo just think Grandpa Gabe's house is haunted. But then the old movie projector in the library opens a passageway to a world of monsters and creatures made of shadows - a place of secrets and dangers set loose when the sun sets. The only weapons to fight them lie in the land on the other side of the Shadow Door...

With the Shadow Door shattered and the passageway closed, Rebecca and Max set out across the dangerous lands of ElseWhere to find a way home. Wherever there is darkness, the Shadow Spies - servants of the Master of Shadows - lie in wait to stop them. Back on the other side of the door, Noah and Theo are working on a rescue. With the clues left behind by Grandpa Gabe and the help of new allies, can they find another passageway and keep the Shadows from destroying our world?

Rebecca, Max, Noah, and Theo are reunited and on the run. The Master of Shadows himself is close behind. Nowhere is safe - monsters lurk in the water and on land, and the Shadow Spies strike at nightfall. All they have to guide them are the strange clues left by Grandpa Gabe. Can the four of them untangle Grandpa Gabes secrets in time? What will it cost them to stop the Shadows?

Trapped in the dangerous world of ElseWhere, Rebecca, Noah, and Theo are possessed by the evils unleashed by the Master of Shadows. Max and Grandpa Gabe may be their only hope of breaking free. But it's a race against time. The Master's plan to destroy both ElseWhere and our own world is in motion... and the hunt to find a new passageway home may come at a terrible cost.

The time has come to confront the Master of Shadows. Rebecca, Max, and Theo must follow Grandpa Gabe into the heart of the Master's realm, the Tower of Shadows. But can Grandpa Gabe be trusted? There's a reason he's so familiar with the dark powers that rule Elsewhere: he created them. Grandpa Gabe's plan might just be a suicide mission, but it's their last chance to save our worldand Rebecca's life.