Episode 1

The season opens on the wreckage. Lucas's betrayal has left Section D reeling, Harry Pearce is on gardening leave, and the new boss is Erin Watts, who has brought Calum Reed with her. There is a lot of new furniture on the Grid, and the old staff are trying to work out who to trust.

Into this steps Ilya Gavrik, Russia's foreign ambassador and Harry's opposite number in the KGB back in the eighties. He is in London to negotiate a major deal between Russia and the UK, the kind of handshake that newspapers put on the front page. What matters to Harry is that Gavrik is the kind of man he has spent a lifetime learning to read. Jonathan Hyde plays him with the courtly menace of a man who has been charming and threatening people in equal measure for decades.

Then Max Witt turns up dead. Max was a retired spy and Harry's colleague from Berlin during the Cold War, and his murder stirs up secrets nobody wanted disturbed. Harry, fresh from winning his employment tribunal and marching straight back onto the Grid, is soon in the thick of it, with Ruth Evershed close behind. The tribunal win is pure Harry: he fights the system, beats it, and walks back in as if the whole detour never happened. Jonathan Brackley and Sam Vincent wrote it, Alrick Riley directed. Peter Firth and Nicola Walker anchor the episode, with Max Brown's Dimitri, Lara Pulver's Erin, Geoffrey Streatfeild's Calum, Shazad Latif's Tariq, Tom Weston-Jones's Sasha, Alice Krige's Elena, Jonathan Hyde's Ilya and Simon Russell Beale's William Towers around them.

It is a reset episode, mostly, one that has to rebuild the team's furniture before it can move, and it is honest about how much of the season's trouble it is still cleaning up. And watching Harry walk back into the building he was forced out of is the best part of it.