Conspirator is a 1949 British film noir, suspense, espionage, and thriller film directed by Victor Saville and starring Robert Taylor and Elizabeth Taylor. Based on the 1948 novel Conspirator by Humphrey Slater, the film is about a beautiful 18-year-old American woman who meets and falls in love with one of a British Guards, an officer who turns out to be a spy for the Soviet Union. After they are married, she discovers his true identity and forces him to choose between his marriage and his ideology. When his Soviet handlers order him to murder his young American wife, he is faced with the ultimate choice. The film was made for distribution by Metro-Goldwyn-Mayer.

This article needs an improved plot summary. (March 2022)

While visiting England, 18 year old Melinda Greyton (Elizabeth Taylor) attends a Regimental Ball where she meets handsome Major Michael Curragh (Robert Taylor). The attraction is mutual and a whirlwind courtship follows.

After the honeymoon is over the young bride finds out her husband is actually a Russian spy. She is frantic and cannot understand. After much discussion Michael decides to give up that life, but soon discovers the party orders him to kill his wife.

• Robert Taylor as Major Michael Curragh
• Elizabeth Taylor as Melinda Greyton
• Robert Flemyng as Captain Hugh Ladholme
• Harold Warrender as Colonel Hammerbrook
• Honor Blackman as Joyce
• Marjorie Fielding as Aunt Jessica
• Thora Hird as Broaders
• Wilfrid Hyde-White as Lord Pennistone
• Marie Ney as Lady Pennistone
• Jack Allen as Raglan
• Helen Haye as Lady Witheringham
• Cicely Paget-Bowman as Mrs. Hammerbrook
• Karel Stepanek as Radek
• Nicholas Bruce as Alek
• Cyril Smith as Detective Inspector
• Janette Scott as Coupie, Aunt Jessica's grandchild (uncredited)

The producers were careful to cut mentions in the film of the British traitors during the Second World War, such as John Amery and Norman Baillie-Stewart, out of fear of litigation by their families.^[2] An indirect mention of Baillie-Stewart remained in the film, however, with him being referred to not by name but simply as "that fellow in the Tower". The plot of the film also bore some similarities to the later case of the Cambridge Spies, including Donald MacLean.

The film created some controversy over the age difference between Robert Taylor, who was in his late 30s, and Elizabeth Taylor, who was 16 at the time of production.^{[citation needed]} When "Melinda" is asked her age by "Aunt Jessica", Elizabeth Taylor's voice says "18", but her lips say "16".

• List of British films of 1949