Del Monroe has been a busy character actor and sometime secondary leading man in television and films from the early '60s through the beginning of the 21st century -- but he is best known for his four-year stint as crewman Kowalski on Irwin Allen's Voyage to the Bottom of the Sea. Born in Santa Barbara, CA, in 1936, Monroe was bitten by the acting bug while serving in the peacetime army of the late '50s, and on returning to civilian life headed for the Pasadena Playhouse, working in repertory with them. He made his screen debut in 1959 in a pair of low-budget quickies, the Edward D. Wood-authored Western Revenge of the Virgins and the crime drama The Girl in Lover's Lane, playing a teenaged mugger in the opening minutes of the latter film. During the early '60s, he moved into television with roles in Westerns such as The Life and Legend of Wyatt Earp and The Dakotas, and the World War II action series The Gallant Men. In between those small-screen efforts, he also got what proved to be a small but very lucrative role in Irwin Allen's feature film Voyage to the Bottom of the Sea (1961), which put the neophyte actor (billed as Delbert Monroe) into the midst of a cast that included such luminaries as Walter Pidgeon, Joan Fontaine, and Peter Lorre. In the movie, he played a brash (and later potentially mutinous) young seaman named Kowalski, and got to do one good scene with Pidgeon. Monroe went on to other work while the movie went on to become a hit at the box office, and a couple of years later, he was called back and cast in the series Voyage to the Bottom of the Sea, being produced by Allen. The series, starring Richard Basehart and David Hedison, ran for four seasons (1964-1968), longer than any non-anthology science-fiction network program until the 1990s. Monroe became a familiar figure to fans as the red-suited crewman Kowalski, his straightforward, unaffected acting style contrasting well with that of the more experienced performers around him. He also squeezed in a few appearances in series such as Gunsmoke and The Time Tunnel (the latter also produced by Allen) during this four years on Voyage. In the late '60s and '70s, he went back to Westerns (Lancer, The Virginian) and, when they disappeared, came to do a lot of supporting roles in crime shows (S.W.A.T., The Rockford Files, Hunter). Monroe also appeared in a few feature films, most notably Phil Karlson's Walking Tall (1973), in which he played a sadistic thug. He left acting for a time in the 1980s, but resumed working occasionally in films and on television, as well as in theater, in the late '90s.