A bubbly, youthful teenaged lead of minor Universal musicals in the 1940s, Donald O'Connor, an excellent dancer and eager clown, later co-starred opposite Gene Kelly and Debbie Reynolds in the now classic "Singin' in the Rain" (1952) and--to somewhat less critical acclaim--a trained mule in the "Francis the Talking Mule" series. His high energy style, boyish manner and engaging lack of ordinary good looks earned him success in adult roles in the 50s but his career slipped abruptly as TV sitcoms killed the market for his more innocent comedies and movie musicals went largely out of fashion.