Despite Detective Superintendent Boyd's mood swings the Cold Case Unit are still in business. Psychological profiler Dr. Grace Foley, Detectives Spencer Jordan and Stella Goodman welcome new pathologist Dr. Eve Lockhart as the team takes on more gripping cases.

Episodes Comprise:

Wren Boys: Boyd and his team re-investigate the mysterious death of a badly beaten teenage boy who drowned 16 years ago in a concrete pit. Linking him to the dumping of another seriously injured teenager in a hospital at around the same time, the team enter the closed world of an Irish traveller community.

Deus Ex Machina: When Khaled Ahmad goes on hunger strike in the UK, Boyd and the Cold Case team are racing against time to find a 19th Century skull. At the same time, MI6 are keen for Boyd to re-investigate the murder of an Iraqi dissident, even though his killer has been tried and convicted.

The Fall: A mummified, sexually conjoined couple fall from a concealed office during the renovation of a city bank. The discovery awakens a fraudulent scandal buried in the city of London around the time of Black Wednesday, but the team soon find they are not the only ones investigating a trail that stretches all the way to Dublin.

Mask of Sanity: When the wallets of his victims surface on the same day he is released from a secure psychiatric unit, the team reinvestigate the work of serial killer James Jenson. However, after turning the spotlight on a second suspect, Dr Bruno Rivelli, and the children's home he previously ran, the team soon find themselves with another murder case on their hands.

Double Blind: Escaped psychiatric patient Daniel Lennon directs a family to unearth a 40-year-old male body in their Hampstead garden. Unable to remember killing his parents, for which he was convicted, Daniel is off his medication, on the run, and has started taking LSD. Meanwhile, the team is distracted as relations between Boyd and Dr. Foley reach rock bottom.

Yahrzeit: The arrival of an anonymous package containing a Nazi SS dagger prompts Boyd to re-open the unsolved murder file of a young girl whose body was found on the street in May 1945 - a case last examined by his ex-colleague Mel Silver shortly before her death.