Jack Larson is a playwright whose work has been performed off-Broadway and at the Edinburgh Festival. And if you pick up a recording of the opera Lord Byron by the 20th century composer, Virgil Thompson, you'll find the libretto was written by Jack.

Oh, yes. Before he picked up his theatrical pen, Jack tried his hand at acting. An early - and his better known - role even received praise from the likes of Sir Laurence Oliver.

And that was...?

Well, among his other accomplishments, Jack co-starred in the 1950's series The Adventures of Superman. He played Jimmy Olsen.

Reference

Superman: From Serial to Cereal, Gary Grossman, Popular Library, (1976). An excellent book which brought Jack (and other co-stars and guest stars) from the series back into the consciousness of a new generation.