Jared Leto, Thirty Seconds to Mars

Since 1998, Jared Leto has been the front man of Thirty Seconds to Mars, a band he formed with his brother Shannon on drums.

Despite Leto’s many acclaimed, high-profile roles in movies such as Requiem for a Dream and Dallas Buyers Club, one could argue that he has been equally prolific (and garnered more fame) as a musician — Thirty Seconds to Mars has released four studio album, three EPs, recorded an MTV Unplugged session, toured the world numerous times, and sold more than 10 million albums.

Jada Pinkett Smith, Wicked Wisdom

While her husband Will Smith created a legacy of radio-friendly hip-hop, Jada Pinkett Smith, surprisingly, is the vocalist of Wicked Wisdom, a nu-metal band she formed in 2002. The band has released albums on Suburban Noize and Interscope, and has toured with Sevendust and as a part of Ozzfest.

Jack Black, Tenacious D

In 1994, years before Jack Black became a famous leading man, he formed the musical comedy duo Tenacious D with Kyle Gass. The band actually helped propel Black to fame as an actor, as it attracted the attention of HBO and led to the duo’s TV series “Tenacious D: The Greatest Band on Earth,” which ran from late 1997 to early 2000.

Tenacious D has also released three studio albums, two EPs, and starred in their own feature film, 2006’s The Pick of Destiny.

Juliette Lewis, Juliette and the Licks

From the late 1980s and throughout the ’90s, Juliette Lewis focused largely on her acting career, which included roles in films such as National Lampoon’s Christmas Vacation, Cape Fear, What’s Eating Gilbert Grape,  Natural Born Killers, and From Dusk Till Dawn, among many others. However, at the age of 30 in 2003, Lewis abrupty shifted her focus to music, founding the band Juliette and the Licks. In six years, the Licks released three full-length albums, and the band’s rotating cast of characters at times included musicians such as Patty Schemel, Craig Fairbaugh, and Dave Grohl, who played drums on the band’s final LP, Four on the Floor.

In 2009, Lewis announced on Myspace that the band would be breaking up. She released her first solo album later that year, Terra Incongnita, which was produced by and included the guitar work of Omar Rodríguez-López of The Mars Volta.

Steven Seagal, Thunderbox

That’s right — in addition to acting and performing martial arts, Steven Seagal has a band. Seagal, who sings and plays guitar, released his first album, Songs From the Crystal Cave, in 2005. The album featured a blend of pop, world music, country, and blues, and included contributions from numerous musicians, including Stevie Wonder.

Seagal released another album in 2006, and tours occasionally with his band, Thunderbox.