A spy is extradited to Britain with an attempt to keep his arrival top-secret. However, the Bulgarians from Batak's homeland who sent him appear to be trying to make his movements as public as possible. When he is eventually murdered, CI5 suspect his music student daughter of poisoning him.

An attempt to start up a street war is launched by a gangland breakaway opposition group, but their leader appears to have an ulterior motive in his actions.

Cowley finds himself under suspicion when a former colleague of his is arrested for being a double agent. So just how deeply involved is the CI5 Chief?

A team of Hong Kong police join CI5 in London to help crack a local heroin supply and protection racket. It's down to Bodie and Doyle to expose a scheme to smuggle drugs to the US by teams of Triads and European agents.

A hitman is employed by a group of East German officials to assassinate a reporter who is planning to publish a report in which their new fighter plane is branded as a potential death-trap.

Silver bullion is being shipped into Britain via the Iron Curtain, only for it to be hijacked by one of the group's own officials.

Various industrial secrets and highly-valuable arts treasures are being stolen and sold on by a gang who are using the blind routine of Customs to their full advantage. CI5 devise a trap to stop the thieves in their tracks.

Whilst investigating a bombing plot Doyle is shot and left for dead in his flat, and as the hospital fights to save his life, he seems unable to decide whether he wants to live or die...meanwhile, Bodie goes on a chase to find Doyle's assailant.