Black Doves will be on Netflix from 5 December. Add it to your watchlist.

“If you don’t get us what we need,” threatens a menacing Keira Knightley, “I’m going to get Sam here to march you to Hampstead Heath and shoot you in the back of the head.” It’s Christmas time but it seems Knightley has firmly left the festive romcoms behind as she takes the lead in the forthcoming Netflix thriller Black Doves.

She stars as Helen, alongside Ben Whishaw, who plays the aforementioned Sam. Both shadowy British spies, their victim in this scene is a kidnapped CIA man called Cole, played by Finn Bennett.

“That true?” asks Cole turning to Sam. “It’ll probably be Richmond Park,” Sam replies.

We’re at Ridgeway Studios in Iver, Buckinghamshire, on day 84 of the 94-day shoot for Black Doves. This not-so-festive scene happens deep into the nonstop, reliably bloody action of this six-part thriller from Joe Barton (Giri/Haji, The Lazarus Project).

The seasonal setting is the only “fun” aspect of a high-speed drama in which Helen’s clandestine life is upended when, after a decade of passing on the secrets of her politician husband (Andrew Buchan), her lover is killed. Cue Sam coming in from the cold at the behest of spymaster Reed (Sarah Lancashire) to help Helen investigate a global conspiracy.

Already commissioned for a second series, this is a spy adventure going places, the momentum baked into Barton’s scripts, with what director Lisa Gunning calls lots of “bang, bang, bang” action. The week after RT visits, they’re heading to suburban south London to film in a 1980s-retro, multi-level nightclub.

“That’ll be crazy,” says Gunning, eagerly. “There’s explosions and balletic fight scenes with two female assassins. They go into this space with 17 gangsters and annihilate them — but in the most beautiful way. It’s like Swan Lake!”