Bernard Samson (Ian Holm) is a marked man following the exposure of his wife, Fiona, as a traitor. Meanwhile, a KGB agent in Mexico wants to defect to the west.

Bernard Samson (Ian Holm) and Gloria are babysitting Soviet defector Stinnes in London, but developments at London Central lead to a deadly turn of events.

Bernard Samson (Ian Holm) has to oversee one last operation to trap the KGB, and to test the sincerity of Stinnes's defection.