In book four of Disrupted Equilibrium, Carly is held captive by Colonel Sebridge and his hybrid pet Ramirez, who uses violence to keep the prisoners in line. Marik's defiance leads to him being infected by Ramirez. When mutants overrun the military base, Sebridge takes Carly and Ramirez with him as he flees with an ancient artifact that calls out to all infected creatures. Cowboy, an enhanced being, is hunted by a Wyrtevore who has stolen his memory. With the help of an old friend, Cowboy finds himself at the gates of a fortress containing the artifact and a quantum computer infused with knowledge from it.

Meanwhile, Luke and Gavin are forced to fight scramblers to the death by a sadistic gang of vigilantes. They find refuge in Hampton Flats where they join the Search & Clear team. When their captor shows up again, Luke suffers another devastating loss.

Genevieve and Chloe arrive at The Mountain to find that her former colleague Sal Bernardi has taken it over with his daughter. An uneasy truce is formed until Conrad and his brother show up to lay claim to it. To save herself and Chloe from Sal's wrath, Genevieve subjects herself to a life-threatening experiment. The infected prove to be powerful adversaries as heroes die and others are changed forever in a fatal game of chess between mortal and monster.