As a lethal powers-enhancing drug is unleashed on the public, Detectives Walker and Pilgrim seek out the criminal mastermind behind it with the help of iconic Power, Retro Girl. As clues come to light, Walker considers the possibility that Wolfe, his dangerous former mentor turned nemesis, might have the answers he seeks.

In the wake of the battle to stop Wolfe, the Powers division gathers to mourn the loss of their fellow officers, while Walker seeks answers about his own future and the possibility of becoming Diamond once again. After seeing the uncertain and dangerous side effects of Sway first-hand Johnny Royalle begins unsavory experiments on known subjects of the drug.