Episode 2

Harry Pearce and Juliet Shaw are at war, politely, inside Thames House. The power struggle between them runs under everything else in the episode, conducted in the polite tones of people who would happily sack each other. Above it, Adam and Zaf are still chasing Shining Dawn, the American extremists behind the opening bomb. Another bomb is out there, the countdown from the last episode still running, and a new ultimatum lands to tighten the screw. The ultimatum from the first episode was never really lifted, just extended. The clock from the opener keeps the whole hour on edge, even before the new threat arrives.

Then Tash disappears, and the suspicion the team has been carrying hardens into something worse: there may be a mole inside the service. Tash's disappearance is the detail nobody can explain, and unexplained things are what the service fears most. Looking for a traitor in your own building concentrates the mind like nothing else, and the episode knows it. A mole hunt changes how people look at each other, and the episode is good at showing that. Corey Johnson's Richard Boyd and Gerald Lepkowski's Joe Kennedy are the Americans who won't go away, while William Armstrong's Alex Roscoe, Peter Brooke's Peter, John Chancer's Monroe and Stuart Sinclair Blyth's Neil fill out the edges. Raza Jaffrey's Zafar and Rory MacGregor's Colin do the running, and their partnership is the most reliable thing in the episode. Anna Chancellor's Juliet and Peter Firth's Harry are the two poles of the hour, and their sparring gives the episode its bite. Ben Richards and David Wolstencroft wrote it; Antonia Bird directed.

The episode keeps two threats in the air: the bomb outside and the traitor inside. They are two ways of attacking the same building. And it never lets you forget which one frightens the team more. It's a chapter that does its job and leaves the story ready for more.