On a visit to the U.K. this September I found a nation gripped by a BBC series called Bodyguard. But I had to fly back to New York, livid and thwarted, before the final episode aired. Thankfully, the show has now hit Netflix in the U.S., and we are soon to discover if America will also thrill to this tale of terrorism, policing, and PTSD.

Bodyguard begins with one of the most electrifying opening episodes of a TV show in recent memory. David Budd (Richard Madden, aka Robb Stark from Game of Thrones) is a beautiful Scottish man on a train to London with his two young children. A rustle of confusion blows through the carriage, and he realizes that something’s up. He informs the train’s conductor that he’s a policeman and former army soldier, and that he can help. There’s been a bomb alert, the conductor stutters, and he takes over. After a tense hunt, Budd finds a young woman in a hijab named Nadia shivering with terror in a bathroom, strapped into an explosive vest.

Budd begs her to trust him, shows her pictures of his young kids. As Nadia sobs and grips her detonator with a shaking hand, he promises that she’ll be okay. Counter-terrorism agents stop the train and level their guns at her. Budd holds Nadia in his arms in a terrifying dance, protecting her from the kill shot.

Budd is hailed as a hero: He has not only saved everybody on the train, but also Nadia, allowing the bomb to be analyzed. We soon realize, however, that all is not well with Police Sergeant Budd. He has untreated PTSD from his time in Afghanistan and is plagued by paranoia, which sometimes is justified, sometimes not. He’s separated from his lovely wife. And although he is swiftly promoted to be a bodyguard to the Home Secretary, Julia Montague, the trouble has only just begun.

The terrorists behind the would-be train bombing are still at large. Montague is reviled by the public for her right-wing agenda on immigration and terrorism. Is she in danger? Is Budd? His kids and estranged wife? A serpentine plot plays out, as the distribution of villainy and heroism shifts between parties. Sometimes the police force are the heroes; sometimes they’re despicable. At other times, it’s the shadowy MI5 that seems to be up to no good. And what about the politicians? The danger level never lets up, echoing the very real atmosphere of sustained tautness that afflicted London in 2017, a year of five terror attacks.

As the six-part series unfurls, we find a conspiracy at its core—a very realistic conspiracy that reflects a nation scarred both by war and the kinds of counter-terrorism responses that produce frightened, vulnerable, violent citizens. No one is above this tangled web, not the police, not the government, and certainly not the people who become terrorists. Everybody is traumatized, and everybody is motivated by the basic desires for love, security, family, and honor.

As Budd, Richard Madden is astonishing. His sweet good looks could have worked against the gravity of his role, but instead they give his tortured psychology a sympathetic appeal. Keeley Hawes, meanwhile, plays Montague with glamorous steel.

The highest praise must go to the two women who play senior police chiefs: Gina McKee as Commander Anne Sampson, head of the Counter Terrorism Command, and Pippa Haywood as Chief Superintendent Lorraine Craddock, Budd’s boss. McKee is probably best known as Bella from Notting Hill, or Judy Molloy from In The Loop. She has a gorgeously long and asymmetrical face, with eyes that are somehow always skeptical. She plays Sampson with such intelligence that there’s no way to tell if she’s a baddie or not until the very last second. Likewise with Haywood, who is trustworthy and reliably gets the work done—but is that just a front?

The series is shot in low colors and grimy, rainy light. When we reach the final showdown, the visual style of Bodyguard breaks through the drama to become its own focus. London itself, in the end, is the star of Bodyguard. There’s no one London, a sprawling city crammed with every type of person, elbow to elbow. But the city has its own look, or ensemble of looks, and as the show goes on it becomes clear how much of London’s aesthetic derives from threats real and imagined.

The city is coated in a sprinkling of security cameras. There have been no trash cans in the Tube system since the era of IRA attacks, and there are bollards everywhere to prevent vehicles mounting the sidewalk. Since moving out of the family home, Budd lives in a block of flats. It is a classic of London architecture, a monument of concrete horizontal lines. “No ball games” reads the sign above Budd’s head, in the instantly recognizable script of London public housing. It’s postwar modernism, the style that filled the void of a bombed-out city. Old bombs, new bombs—it’s all London.

David Budd’s beautiful face and ravaged mind are front and center in Bodyguard, but behind him is an imperiled city full of people wrestling with an invisible, ever-present danger. Everybody is cracking under their thin shell of performed normality, while the rain falls and the gray pavements stretch out endlessly before them.