Criminal Minds Episode 3.10 True Night

The team arrives in Los Angeles to cover the crimes of a serial killer in the midst of a psychotic break. Multiple brutal murders have occurred in a two week span, and the team focuses on a three block radius surrounding the scenes. Soon, six gang-bangers turn up dead in a nearby neighborhood, with the gang leader missing. The MO is the same as the other murders, which means the killer has ventured out of his territory for a reason.

Meanwhile, Jonny McHale, a young, famous comic book author is going through a breakdown of his own. He experiences constant flashbacks of being with a woman, Vicki, who was pregnant. They were happy and deeply in love, but now she refuses to return his calls. His comic work has become more violent of late, and his manager takes his new drawings to the police. He thinks Jonny is sick, and it turns out that he's right.

The team discovers that a bunch of thugs, led by Glen Hill, the head of the gang, killed Vicki and nearly eviscerated Jonny six months before. They capture Jonny, who has no memory of the killings, or of Vicki's murder. It's only when he's confronted with the facts of his recent tragedy that he confesses and reveals the location of Glen Hill. The gang leader is dead, but he suffered dearly beforehand.