Johnny and Clyde, a pair of serial killers who are madly in love, set their sights on robbing a prosperous casino.

Pitted against his most chilling adversary yet, Luther is haunted by past ghosts and hellbent on revenge as the Serious Crime Unit faces its most challenging psychological duel to date. There is no question he will come close to the edge, but will he finally go over?

Niki harbors a secret dark side, cheerleader Claire heals from any injury, Japanese Dilbert Hiro can bend time and space, Senatorial candidate Nathan is able to fly, his brother Peter can copy others' powers, Matt is a cop who can read minds, and junkie artist Isaac sees the future. While Claire and Hiro explore the potential of their new powers. Niki and her son try to elude some hired thugs and end up overwhelmed by her dark side. Suresh searches...