Red Joan turns an incredible espionage story into a lethargic and boring film. Melita Norwood was a British woman who spied for the Soviet Union during and after World War II. The information she smuggled was directly responsible for the Soviets acquiring the atomic bomb. Red Joan, adapted from the novel by Jennie Rooney, is a fictional account based on Norwood's activities. What should be a riveting thriller is told with a plodding delivery.

Dame Judi Dench stars as the older Joan in modern times. A white-haired, genteel grandmother, she is arrested by the British government for espionage and treason. Her son (Ben Miles) is outraged by the charges. This must be a mistake. His mother spent her life as a librarian. It's only when he sits through her interrogation is the shocking truth revealed.

Sophie Cookson co-stars as the younger Joan. In the mid thirties, she was a reserved student studying physics at Cambridge. The only woman in her class, she meets the vibrant, sexually uninhibited Russian, Sonya (Tereza Srbova). Joan is taken by Sonya to a meeting of communists. She is captivated by the magnetic presence of Sonya's cousin Leo (Tom Hughes), a diehard Marxist and Stalinist. When the second world war breaks out, Joan is sent to work as an assistant to a critical government scientist (Stephen Campbell Moore). Her access to the British atomic weapons program made her an invaluable asset as a Soviet spy.

Red Joan is ninety percent flashback. Sophie Cookson has nearly all of the screen time as young Joan. Judi Dench isn't given anything to do, but look down or away wistfully as the character remembers her youthful transgressions. She's essentially wasted in the film. This isn't a knock on Cookson's performance. She does well with the tepid material given. There's just a huge imbalance to the plot. Famed theater director Trevor Nunn, who's won numerous awards on the West End and Broadway, needed to spread the wealth between the actresses. It's odd to have Judi Dench and underuse her. The granny next door being outed as a Russian agent is a helluva surprise. Red Joan doesn't spend nearly enough time on the fallout or reasons for her capture.

Joan's romantic relationships are the primary arcs, not the actual spying. This is understandable to a point. Her infatuation with Leo was the gateway to treachery. Trevor Nunn and screenwriter Lindsay Shapero get too embroiled in melodrama. The best scenes in the film are Joan trying to cover her tracks and investigating the depths of the spy ring. These moments have decent tension, but are fleeting. Then we have her pining over lovers entanglements. There was meat on the bone for a crisp, multi-layered storyline. Her betrayal was instrumental in evening the atomic scoreboard. Red Joan mildly explores her political motivations. What we get is a drab soap opera with a sprinkle of espionage.

An opportunity was missed for a far more engaging film. Red Joan has an able cast, but the film doesn't do their performances justice. It's a bummer seeing Judi Dench, who was so forceful as M in the Bond films, regulated as a meek secondary character. Red Joan is distributed in the US by IFC Films.

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