William Eythe (April 7, 1918 – January 26, 1957) was an American actor of film, radio, television and stage.

Born in Mars, Pennsylvania, a small town located about 25 miles from Pittsburgh, he was interested in acting from a young age. He attended Carnegie Tech University and studied acting and he began writing his own plays. "Lend An Ear," was one of his early plays and proved to be a theatrical success, later going on to have a Broadway run.

Eythe eventually moved to New York City, where he got various jobs performing in radio dramas and as an announcer for a local television station. During the Second World War, many of Hollywood's young male stars were away at war, and the film studios were forced to locate newer, younger actors who were below the age of military service, or those actors who were considered unfit for service due to medical conditions. Eythe, who had poor hearing, was one such actor, and he was spotted by a talent scout for 20th Century Fox films.

He was given a screen-test, and landed a role in the film The Ox-Bow Incident, which co-starred Henry Fonda and Dana Andrews. In 1943, he starred opposite Jennifer Jones in the Academy Award-winning film The Song of Bernadette. Eythe's star was rising fast in Hollywood, and he acted in films with such stars as Anne Baxter, Vincent Price, and Tallulah Bankhead.

The Hollywood publicity machine linked Eythe with many of the hottest young stars in Hollywood of the time, such as Anne Baxter, June Haver, Margaret Whiting, and others, but in real life Eythe was gay. Eythe was involved in a relationship with the actor Lon McCallister, a very popular young screen actor at the time. When a movie fan magazine published photos of Eythe and McCallister together, Darryl F. Zanuck, president of 20th Century Fox was furious, and as punishment sent Eythe to England to film the movie "Meet Me At Dawn". Eythe was badly miscast in this film as a duelist, which was the first film to be shot at the new 20th Century Fox Studios in England. When McCallister joined Eythe in London, and their photos together made the papers, Zanuck cancelled Eythe's contract at Fox.

In, seemingly, a state of panic, Eythe quickly married a young 20th Century Fox contract actress, Buff Cobb. The marriage was short lived and was not a happy one, and the couple would soon divorce. Later Cobb would sue Eythe for support payments, which would lead to Eythe's later arrest. Cobb later went on to marry newscaster Mike Wallace.

Among his films are two directed by Otto Preminger, "Centennial Summer" and "A Royal Scandal," in which he co-stars very effectively with Tallulah Bankhead, Anne Baxter and Charles Coburn.

After being dropped from Fox, Eythe was able to do some work on television, and an occasional B-movie for Paramount or Columbia Pictures, but he primarily focused on theatre work. Eythe was influential in the career of Carol Channing, starring with her in the Broadway revue "Lend an Ear" in 1948. He also appeared in a starring (though non-singing) role in the 1950 Cole Porter musical "Out of this World," based on the Greek myth of Amphitryon, in which Jupiter (George Gaynes) comes to earth to bed a lovely young lady, taking the shape of her much-loved husband (Eythe).

His later years were not happy ones. Arrests for drunken driving and a covered up arrest for solicitation in a New York City Subway restroom clouded his later years. Through it all Eythe lived a fairly open lifestyle and carried on his relationship with his long term partner McCallister. In later years Eythe and McCallister would travel throughout the world taking home movies. These color films would later be sold to various film studios as stock shots.

Eythe died of hepatitis in Los Angeles in 1957 at the age of 38.