Rising to fame as an MTV VJ, Rex later became an actor known for What I Like About You, starring in three films of the Scary Movie franchise, and National Lampoon's Pledge This!.

Rex was born in San Francisco, California, and raised in Alameda,[2] the son of Zoe, an environmental consultant, and Paul, a relationship coach.

At age 18, he was attending community college and working at a potato-sack factory when he began dating and living with a model in Oakland.

Rex more recently starred alongside comedian Nick Swardson in the Comedy Central show, Typical Rick, which ran for two seasons from 2016 to 2017.

[18] Rex adopted his alter ego Dirt Nasty[19] and formed the rap group Dyslexic Speedreaders with Avalon & Andre Legacy.

[21] Rex was an investor in the New York City nightclub The Plumm with partners Noel Ashman, Samantha Ronson, Chris Noth, and others.

[22] In 2007, Dirt Nasty released his self-titled debut album which included the songs 1980, Cracker Ass Fantastic & Dropping Names.

[26] Dirt Nasty appeared in Season 1, episode 5 of Paris Hilton's My New BFF where the girls had to play "Seven Minutes in Heaven" with him.

[29] In October 2021, as a result of the attention Red Rocket had garnered, Rex signed with the management firm Range Media Partners.

He was living in a guesthouse in the Venice neighborhood of Los Angeles when he was offered US$70,000 by British tabloids to falsely claim he had dated Meghan Markle, his co-star in Cuts.