1. Luther returns to duty seven months after an incident caused him to be suspended and suffer a nervous breakdown. On his first day back, Luther has to prove a double murder by discovering the killer's motive.
2. Luther has to stay ahead of a killer who is trained in using sniper weapons and has been murdering police officers. Luther struggles to discover the shooter's true motivation, which is tied to his war veteran father.
3. Luther must catch a serial killer who kidnaps mothers every decade and drains them of their blood for satanic purposes. He must use all of his abilities to stop him from killing his latest victim.