Known for his blonde hair and well-trimmed moustache, Mull was born in Chicago, raised in Ohio and Connecticut and studied art in Rhode Island and Rome. He combined his music and comedy in hip Hollywood clubs in the 1970s.
“In 1976 I was a guitar player and sit-down comic appearing at the Roxy on the Sunset Strip when Norman Lear walked in and heard me,” Mull told The Associated Press in 1980. “He cast me as the wife beater on Mary Hartman, Mary Hartman. Four months later I was spun off on my own show.”
In the 1980s he appeared in films including Mr Mom and Clue, and in the 1990s had a recurring role on Roseanne.
He would later play private eye Gene Parmesan on Arrested Development, and would be nominated for an Emmy in 2016 for a guest turn on Veep.
“What I did on Veep I’m very proud of, but I’d like to think it’s probably more collective, at my age it’s more collective,” Mull told the AP after his nomination. “It might go all the way back to Fernwood.”
Other comedians and actors were often his biggest fans.
“Martin was the greatest,” Bridesmaids director Paul Feig said in an X post. “So funny, so talented, such a nice guy. Was lucky enough to act with him on The Jackie Thomas Show and treasured every moment being with a legend. Fernwood Tonight was so influential in my life.”