Born in 1928 in Los Angeles, Larson’s film debut was in the 1948 war movie “Fighter Squadron.” Intent on becoming a Broadway actor, he only reluctantly took the role as cub reporter and photographer Jimmy Olsen on "The Adventures of Superman." Afraid of being typecast, he agreed to appear in the series only after his agent convinced him the show was unlikely to be aired. The opposite happened, and "The Adventures of Superman" would air in syndication from 1952-1958.
Larson’s fears proved correct – when Superman ended, he found his ability to get new acting work severely limited by his association with the show. Encouraged by friends, he switched career paths, focusing on behind the scenes work and eventually forging a successful career as a librettist, playwright and producer. Among his plays are "The Candied House" (1966) "Chuck" (1968) and later in life, "The Astronaut’s Tale" (1998).
However, despite the role hurting his acting career, Larson never distanced himself from association with "The Adventures of Superman." Throughout his life he recalled it with fondness, and gave many interviews. He would often appear in cameo roles that mentioned his time as Jimmy Olsen, including an episode of "Lois & Clark," the short-lived early 90s series "Superboy," and an American Express commercial with noted Superman fanatic Jerry Seinfeld.
Larson’s long term romantic partner was director James Bridges. The two were together from 1958 until Bridges death in 1993.