Through Mullen's support at various nightclubs in California, the scene gave birth to such bands as the Red Hot Chili Peppers, The Go-Go's, X, The Weirdos and the Germs.

[citation needed] In 1977, Mullen founded The Masque, a small punk rock club in central Hollywood, California, which existed intermittently from 1977 to 1979.

[1] Fire marshals sued Mullen to end the lease and many bands came to his aid with two nights of benefit concerts to raise money to pay legal fees.

[1] Club Lingerie was known more for its eclectic bookings that ran from punk and pop to jazz and blues, as well as the first West Coast appearances by several New York-based hip-hop acts.

On October 12, 2009, the website Media Bistro reported that Mullen had been rushed to a Los Angeles hospital, having suffered a serious stroke.

[3] At the time of his stroke, Mullen was celebrating his 60th birthday by traveling through Santa Barbara and Ventura with Kateri Butler, his companion of 16 years.

'[4] Red Hot Chili Peppers bassist Flea wrote a two-page article for the Los Angeles Times on the passing of Mullen.