Thirty years after the death of a suspected terrorist, the man's daughter receives an anonymous note claiming he was murdered, Clues lead the team to the Greenham Common anti-nuclear prostests of the 1980's. Sasha had dinner with Ned, who's angling for a reconcilliation

When the discovery of a film critic's body in a sewer relates to the unsolved murder of an artist 20 years earlier, Sasha must work with her ex again. Ned's team tackles the latest crime, while UCOS digs into the cold csase. Danny's knowledge of underground London may be the key to solving both.