During a handover to the head of counter-terrorism of MI5, Harry Pearce, a terrorist escapes custody. When Harry disappears soon after, his protégé is tasked with finding out what happened as an impending attack on London looms, and eventually uncovers a deadly conspiracy.
Peter Firth
as Harry Pearce
Kit Harington
as Will Holloway
Elyes Gabel
as Adem Qasim
Jennifer Ehle
as Geraldine Maltby
Tim McInnerny
as Oliver Mace
Tuppence Middleton
as June Keaton
Eleanor Matsuura
as Hannah Santo
David Harewood
as Francis Warrender
Lara Pulver
as Erin Watts
Hugh Simon
as Malcolm Wynn-Jones
Ronan Summers
as Ed Lansbury
Elliot Levey
as Philip Emerson
