Those Who Kill (2014): Season 1, Episode 8

1 - 8: Insomnia

A killer uses enhanced hallucinogens in his methods, causing the team to work with the Narcotics Division and Catherine's former lover. Meanwhile, Thomas must revisit a case from which he based his book, as he receives post cards from the killer. Also, Catherine's mother is hospitalized after apparently having a stroke and falling down the stairs at home. Her condition worsens, and her family must make a difficult decision.