Someone has just tried to kill Stephen Fisher, and Strickland may be next. Thirty years earlier, both were part of a group involved in a covert operatioon for MI-5. Other members of the group are already dead, Stricklad turns to Sandra ad her team for help

Strickland sends Gerry and Steve to Glasgow to help with the formation oa a new Unsolved Crime and Open Case Squad. Once there, the two are caught up in a case from 1993, the still-unsolved murder of a wealthy bookie, and Steve comes face-to -face with an old adversary.

In 2007, Max Klein, an East German immigrant, bled to death. His mysterious last words were "blue flower". Piecing together his story, the team learns that Klein once had connections with the Stasi, East Germany"s dreaded secret police. But did he work for them or against them?

The team reopens the case of Sean Docherty, a talented younf Belfast poet whose burned body was discovered 10 years ago in a known gangster's scrapyard. Gerry believes the murder was realted to Sean's cruiminal connections but Brian is sure the answer les in his poetry

Two years earlier, 16 year old tennis champion Alice Kemp fell to her death from a balcony after losing a crucial match. Did she jump, or was she pushed? As the ream looks for answers, Gerry wonders if he did enough to encourage his own daughter's sports ambitions.

The body of a computer expert turns up in the wrong place--the morgue of a teaching hospital--under a false name. The case pulls the team into the high-tech world of online hacktivism, and Brian has a hard time accepting Steve as the new team member

In 2003, a 17-year-old girl went missing in Scotland and was presumed dead. When her DNA turns up at the scend of a recent London robbery, retired Glasgow detective Steve McAndrew aarrives to help. A bundle of Scottish energy, he immediately ruffels feathers,

Did a young diplomat commit suicide, or was she murdered? She had suffered personal tragedy and professional disgrace shortly before her death, but Sandra isn't convinced. Ignoring warnings from her boss, Sandra explores a possible cover-up at the Foreign Office

When a body is found near an elite boarding school, the team reinvestigates the disappearance of a young PE teacher five years earlier. Preparing for a visit from a prominent MP, the school isn't very helpful. Brian, meanwhile, struggles to keep a secret.

Shadowy Whitehall intellegence figure Stephen Fisher arrives to tell the team about their coldest case so far: a 160-year-old murder. Then Jack stuns trhe others by announding that he's quitting.