Robert Hudson Walker (October 13, 1918 – August 28, 1951) was an American actor[1] who starred as the villain in Alfred Hitchcock's thriller Strangers on a Train (1951), which was released shortly before his premature death.

Emotionally scarred by his parents' divorce when he was still a child, he subsequently developed an interest in acting, which led his maternal aunt, Hortense McQuarrie Odlum (then the president of Bonwit Teller), to offer to pay for his enrollment at the American Academy of Dramatic Arts in New York City in 1937.

[citation needed] While attending the American Academy of Dramatic Arts, Walker met fellow aspiring actress Phylis Isley, who later took the stage name Jennifer Jones.

Walker's charming demeanor and boyish good looks proved popular with audiences, and he was promoted to stardom with the title part of the romantic soldier in See Here, Private Hargrove (1944).

[5] Returning to MGM, Walker appeared with Spencer Tracy and Van Johnson in Thirty Seconds Over Tokyo (1944), the true story of the Doolittle Raid.

Walker starred as a GI preparing for overseas deployment in The Clock (1945), with Judy Garland playing his love interest in her second non-musical film.

[6] He starred as composer Johannes Brahms in Song of Love (1947), which costarred Katharine Hepburn and Paul Henreid, but the lavish production lost MGM more than $1 million.

He also appeared in a film about the construction of the atomic bomb, The Beginning or the End (1946), which also resulted in a loss at the box office, and a Tracy-Hepburn drama directed by Elia Kazan titled The Sea of Grass (1947), which was profitable.

[7] Back at MGM, Walker starred in two films that lost money, Please Believe Me (1950) with Deborah Kerr and The Skipper Surprised His Wife (1950) with Joan Leslie.

[8] Following his discharge, he was cast by director Alfred Hitchcock in Strangers on a Train (1951), for which he received acclaim for his performance as the charming psychopath Bruno Antony.