David Hare concludes his trilogy of films about MI5 renegade Johnny Worricker with another fugue on power, secrets and the British establishment. Johnny Worricker goes on the run with Margot Tyrell across Europe, and with the net closing in, the former MI5 man knows his only chance of resolving his problems is to return home and confront prime minister Alec Beasley.

Johnny is a long-serving MI5 officer. His boss dies suddenly, leaving behind an inexplicable file which threatens the stability of the organisation.