Investigating the disappearance of an old college friend, Will finds himself caught in an underground fight club where the combatants are genetically engineered abnormals who fight to the death like modern day gladiators.

Abnormals in remote regions are subjected to an airborne biological agent that compels them to launch a violent string of murders

The Five, led by Magnus, attempt to find the secret labyrinth in the decimated city of Bhalasaam. Once located, they must complete a series of cryptic tests that can only be achieved using each of their unique powers.

The search for Ashley puts Magnus and her allies in the path of Kate Freelander (Agam Darshi), a con artist with ties to the Cabal who divulges the location of a secret facility

The Cabal's new "Super-Abnormals" begin destroying Sanctuaries around the world. It won't be long before they launch their attack on the Old City Sanctuary, and Magnus must choose between saving Ashley and saving the Sanctuary Network.

With chaos all around them, the team must come to terms with how to rebuild after the Cabal’s attacks. Magnus takes a methodical approach to prove Ashley is still alive, while Will and Henry take on the daunting task of processing the hundreds of Abnormals who now seek refuge at the Sanctuary.