Appearances

Title	Role	Year	Approx. Age
Peter Lundy and the Medicine Hat Stallion	Muggeridge	1977	54
Time of Your life	Dudley	1948	25
Henry Aldrich, Boy Scout	Henry Aldrich	1944	21
Little Men 1940	unknown	1940	17
Tom Brown's School Days (1940)	Tom Brown	1940	17
Back Door to Heaven	Frankie	1939	16

In 1932, Jimmy Lydon's father, who was an alcoholic, decided to retire from working. This decision forced all of the other family members to seek employment in the depths of the Great Depression. By 1937, Fourteen-year-old Jimmy, not knowing what he wanted to do, tried his hand at acting. His first role was Danny in the Broadway play Western Waters.

He had been allowed to audition for the part after fabricating a list of roles he had previously portrayed. In the next couple of years, he learned the acting craft while performing in plays such as Sunup to Sundown, Prologue to Glory, Sing Out the News, and The Happiest Days. In 1939, he moved with his family to Hollywood to seek film roles.

One of his first starring roles was the title character in the 1940 movie Tom Brown's School Days, also starring Cedric Hardwicke and Freddie Bartholomew. The film was well-received by critics, with Variety praising it in a January 1940 review as "sympathetically and skillfully made, with many touching moments and an excellent cast". Lydon was called "believable and moving in the early portions, but too young for the final moments".

Between 1941 and 1944, under contract to Paramount Pictures, Lydon starred as the screechy-voiced, adolescent Henry Aldrich in the movie series of that title. After completing the Aldrich series, the now 21-year-old Lydon signed a contract in 1944 with Republic Pictures. He appeared in the acclaimed 1947 film Life with Father in the role of college-bound Clarence. Variety called Jimmy Lydon's portrayal "effective as the potential Yale man". He then appeared opposite James Cagney in the 1948 movie The Time of Your Life. From 1949 to 1950, he and Janet Waldo voiced the leading characters in the radio comedy Young Love.

Lydon easily gained roles in the new medium of television. He portrayed Chris Thayer on The First Hundred Years. The show was CBS' first daytime soap opera. It was performed live for three seasons of 300 episodes. In 1953, he was cast as Murray in the aviation adventure film Island in the Sky, starring John Wayne. He also played Biffen Cardoza on the last six episodes of Rocky Jones, Space Ranger in 1954 and made appearances in Lux Video Theatre and The Christophers. In 1955, he appeared on Sergeant Preston of the Yukon as Johnny Lane, plagued by cabin fever, in the episode titled "The Williwaw".

In 1958, Lydon played the role of Richard in Anne Jeffreys' and Robert Sterling's short-lived sitcom Love That Jill. Lydon appeared in guest roles on Crossroads, Casey Jones, The Life and Legend of Wyatt Earp, Wagon Train, Hennesey, The Twilight Zone, and Tales of the Texas Rangers, as Lt. Jared Evans in the 1958 episode "Warpath". A year later, he guest-starred on the television series Colt .45. Lydon played the role of Willy in the episode "Return to El Paso", with Paul Picerni cast as Jose.

After working increasingly in television in the 1950s, he turned to production and helped to create the detective series 77 Sunset Strip, as well as the sitcom M*A*S*H. He also produced the television adaptation of the film Mister Roberts in 1966 and Roll Out in 1973?1974. Lydon played Captain Henry Aldrich (a reference to his Aldrich movie series) on the latter show.

In 1963, Lydon was working for Warner Brothers to place the western series Temple Houston on the Fall schedule. On orders from studio boss Jack Webb, episodes were put together in two or three days each, something previously thought impossible in television production. Work began on August 7, 1963, with the initial airing set for September 19. Lydon recalls that Webb told the staff: "Fellas, I just sold Temple Houston. We gotta be on the air in four weeks, we can't use the pilot, we have no scripts, no nothing - do it!" Lydon recalls the team having worked around the clock to get Temple Houston on the air. Co-producer William Conrad directed six episodes, two scripts simultaneously on two different soundstages at Warner Brothers: "We bicycled Jeff (Jeffrey Hunter) and Elam (secondary character Jack Elam) between the two companies, and Bill shot 'em both in four-and-a-half days. Two complete one-hour shows!". Although the production challenge was met with much difficulty, Temple Houston never gained popularity in the ratings and ended after 26 weeks. At the same time, script and cast changes that Webb had imposed on 77 Sunset Strip caused the cancellation of that series before it could finish its sixth season.

During the 1970s & 1980s, Lydon continued to act on television, with roles on episodes of Gunsmoke, Lou Grant, Simon & Simon, and St. Elsewhere.

Lydon did not enjoy the Hollywood experience as a juvenile. He appeared on Broadway and in films initially to help support an alcoholic father and family of nine children. He had practically no education as a result. He gave a 15-year-old Elizabeth Taylor her first screen kiss in Cynthia (1947).

Personal quote: 'I don't like to see any kids on stage or screen. It's unnatural."

Lydon died at the age of 98 on March 9, 2022, at his home in San Diego, California. He is survived by two daughters.