The Women of Arlington Hall

In September 1947, recent Radcliffe graduate Catherine “Cat” Killeen arrives at Arlington Hall in Virginia for a top-secret government job. During orientation, Cat and other new recruits, including her new friend Effie LeBlanc, sign secrecy oaths, warned that treason is punishable by execution. Cat’s interviewer Margaret reviews Cat’s FBI background check, which notes she called off her wedding to Andrew Foley on the morning of the ceremony. The check also flagged her maternal uncle, Peter Walker, a Columbia University physics professor and member of the Communist Party. Cat, whose mother was disowned for marrying a poor Irish Catholic, has never met her mother’s family. After her interview, Margaret assigns her to a unit in Building B. Effie helps Cat secure a room at the Arlington Farms women’s dormitories.

At Building B, Gene Grady welcomes Cat to the “Russian section,” a unit dedicated to breaking the Soviet code system to identify spies in the US. While out with Effie and another dorm resident, Dale Motlow, Cat runs into Jonathan Dardis, her arrogant Harvard rival from a cryptology seminar. He reveals he turned down the Arlington Hall job, which Cat realizes was offered to him first, and is now an FBI agent. Jonathan is the man Dale has been admiring from afar. Cat meets two other women from the Russian section, Gia Manzo and Rosemary Biddle, and feels a pang of jealousy when Jonathan dances with Dale.

A few weeks later, Cat passes her final training exam with Gene. The head of the Russian section, Meredith Gardner, calls an urgent meeting where he reveals a deciphered 1944 KGB message containing the names of 17 top scientists from the Manhattan Project. This proves the Soviets had spies who knew about the atomic bomb. Frank Richards, the chief of the intelligence division, announces the team will compile a special report for high-level officials. Later, at the Cairo Hotel, Cat and Jonathan dance, and she explains her reasons for calling off her wedding. The team’s work is officially codenamed the Venona Project. Cat is assigned to create a master book of all discovered code names. While working late, she spots a linguistic advisor, Bill Weissman, acting suspiciously. She also uncovers a clue in a message about the spy “Liberal,” revealing his wife’s real name is Ethel.

In a high-level meeting, J. Edgar Hoover assigns FBI agent Bob Lamphere to work with Meredith’s team. Meredith resists but is overruled. Lamphere mentions Jonathan is on his team. Meredith initially stonewalls the gregarious Lamphere, but Cat and Rosemary confront him, and he agrees to cooperate. He tells Cat the most useful thing the FBI could provide would be uncoded, plain-text copies of 1944 Soviet messages from New York, which he believes are impossible to obtain legally. Cat relays this to Jonathan, and they make a bet: If he gets the messages, she must sing with the band at the Liberty Pub. Just before Christmas, Bob and Jonathan deliver the files, which they obtained through a covert operation. Meredith is initially furious with Cat for overstepping and threatens to fire her, but he ultimately agrees to review the files over the holiday break. At a party, Cat sings with the band and notices Weissman talking with Lindsay Philmore, a high-ranking British intelligence official. Later, Jonathan and Cat almost kiss but are interrupted, and an overwhelmed Cat leaves without saying goodbye.

In January 1948, Meredith reveals the files were a “jackpot.” At a meeting with Bob and Jonathan, he announces the cover name for the Soviet atomic spy plot is “Enormoz.” Bob then reveals Jonathan has been promoted and transferred to London. On his last night, Jonathan takes Cat to see the Ink Spots. He calls them “star-crossed” but hopes they will find each other again. They share a passionate kiss goodbye.

Eighteen months later, in August 1949, the Venona Project has successfully re-created the KGB codebook, leading to the arrest of spy Judith Coplon. Cat’s correspondence with Jonathan has dwindled. Bob Lamphere informs the team that the Soviets have successfully tested an atomic bomb. The news demoralizes everyone, but Meredith rallies them. The team identifies scientist Klaus Fuchs as the spy codenamed “Rest,” their first major breakthrough in the atomic spy ring. Bob also reveals Jonathan is transferring back to the US, but to the New York City field office. At a party, Cat overhears a drunk Lindsay Philmore telling Weissman he is worried a man named “McAllister” could destroy him. Philmore then confronts Cat, making a threatening comment about her uncle. Jonathan makes a surprise appearance, but the reunion is awkward, and Cat leaves the party with another man to create distance and signal to Jonathan that she has moved on.

In February 1950, newspapers announce the arrest of Klaus Fuchs. Jonathan urgently meets Cat at the Lincoln Memorial and reveals the FBI is tailing her. Philmore and Weissman have accused her of espionage, providing fabricated evidence of contact with her uncle, Peter Walker. An anonymous tip has also identified Walker as a Soviet agent, codenamed “Quantum,” which Meredith has confirmed through Venona messages. Realizing she is being framed, Cat decides to go to New York to confront her uncle. Jonathan helps her plan the secret trip.

In New York, Cat meets Peter Walker, who confesses to being a spy but agrees to help clear her name. That evening, he introduces her to his friends, Julius and Ethel Rosenberg, whom Cat immediately suspects are “Liberal” and his wife. The next morning, Cat finds the FBI raiding Peter’s office, but he has fled the country. Bob Lamphere takes Cat in for questioning, and Jonathan is suspended for helping her. That night, Jonathan visits Cat at her hotel, and they spend the night together, declaring their love. The next day, a package from Peter arrives at the FBI. It contains a notarized letter exonerating Cat and photographs that corroborate Venona clues, implicating Philmore, Ron McAllister, Julius Rosenberg, and another man named David Greenglass in espionage. Cat is freed, and she returns to Arlington Hall, where she is reinstated. Weissman is arrested as a mole in Building B, while Philmore and McAllister are reported to have defected to Russia.

Six months later, in August 1950, Jonathan has been punitively reassigned to El Paso, Texas. The entire Rosenberg spy ring has been arrested. Meredith and Bob express concern that Ethel is being prosecuted primarily to pressure Julius, as the evidence against her is weak. While on a weekend trip with her friends at Rosemary’s family beach house, Cat decides to travel to El Paso to be with Jonathan. Just as she makes her decision, Jonathan unexpectedly arrives, having left his post to be with her. He declares his love and promises he is not leaving her again. They drive off together in his convertible, ready to start their future.