A gruesome serial killer is terrorizing London while brilliant but disgraced detective John Luther sits behind bars. Haunted by his failure to capture the cyber psychopath who now taunts him, Luther decides to break out of prison to finish the job by any means necessary.

A dysfunctional family that can't seem to get along and get it together reluctantly reunites for a family wedding. As their many skeletons are wrenched from the closet, it turns out to be just what this singular family needs to reconnect.

Guests at a housewarming party are slipped a mysterious drug. When ugly truths start to emerge, chaos reigns and threatens the relationships of old friends.