Less than two decades after Nazi Germany went down to defeat in World War II, the National Socialist Movement, a British neo-Nazi party headquartered in London, garnered notoriety through rallies, marches and antisemitic attacks. Ridley Road, a four-part BBC Masterpiece series being presented by the PBS network every Sunday until May 22, skillfully resurrects this period. Inspired by true events, based on a book by Jo Bloom and directed by Lisa Mulcahy, this period piece is set in 1962. The National Socialist Movement, a fringe group at best, was led by Colin Jordan, a Cambridge University graduate and former high school teacher. Jordan, played with cool detachment by Rory Kinnear, was an admirer of Oswald Mosley, the head of the British Union of Fascists in the 1930s, and an associate of George Lincoln Rockwell, the leader of the U.S. Nazi Party. In Ridley Road, two British Jews, Jack Morris (Tom Varey) and Vivien Epstein (Agnes O’Casey), infiltrate Jordan’s organization with the objective of exposing it as a paramilitary group subject to prosecution by the government. They are recruited by Vivien’s uncle, Solly Malinov (Eddie Marsan), a taxi driver and an anti-fascist who remembers Mosley’s blackshirts with dread. Jack and Vivien are old lovers who rekindle their romance after she rejects an arranged marriage her parents have set up for her. Having disappointed them, Vivien leaves her home in Manchester and decamps in London, where she finds a job as a hairdresser. Walking back to her flat one day, she passes a neo-Nazi rally and hears one of the hooligans shouting, “Perish Judah.” Much to her surprise, it is Jack. As she later learns, Jack has been “passing” as a mole in Jordan’s ragtag outfit. Although she is not a “political person,” Vivien joins Solly’s anti-fascist group after neo-Nazis set fire to a Jewish school, resulting in the death of one of its students. Dying her brown hair blonde and assuming a pseudonym, she secures a meeting with Jordan, who lives in a large residential building with his young son Paul. The ostensible reason for her visit is to find Jack, who has mysteriously disappeared. Jordan, a remote and earnest man, greets her with suspicion. His hard demeanor melts as Vivien tells her fictitious personal story. In particular, Jordan is impressed by her “intelligent eyes.” He, in turn, explains that his raison d’être is “to protect” Britain from “foreign invaders” and other undesirables changing its demographics. Emboldened by his rhetoric, Vivien mouths racist slogans and expresses an interest in joining the cause. Having won Jordan’s confidence, Vivien is driven to a country estate loaned to him and his followers by a British aristocrat. There she meets Jack, who’s recovering from injuries sustained in a melee. O’Casey and Varey acquit themselves with aplomb in their respective roles. In the next two scenes, Vivien finds an antisemitic pamphlet in her landlady’s apartment that reads, “Free Britain from the Zionist Conspiracy,” while several neo-Nazi thugs, bats in hands, roam a Jewish cemetery with the apparent intention of damaging headstones. At her second meeting with Jordan, Vivien softens him up with flattery. Jordan is married to a haughty French woman, but their relationship is on the rocks. In the meantime, Jack plants a listening device under Jordan’s desk. In another scene, Rockwell (Stephen Hogan), the American fascist, salutes Jordan as a real leader to whom he defers. A local rabbi thinks the police should investigate Jordan’s movement, but when Solly meets a detective to argue the case, he proves to be uncooperative and even obstructive. A viewer is left with the feeling that some policemen may have been sympathetic to Jordan’s ideas. Indeed, police are nowhere to be seen as a mob of neo-Nazis, carrying placards reading “Free Britain From Jewish Control,” converges on a synagogue. As Vivien grows closer to Jordan, she seduces him and finds incriminating documents in a suitcase. Vivien eventually falls afoul of Jordan and his crowd, compelling her to flee, with Jordan and his minions in hot pursuit. Ridley Road is riveting from start to finish, drawing a vivid portrait of a neo-Nazi subculture that, for a relatively brief moment in time, attracted some attention in 1960s Britain.