Mutant Enemy Productions is the production company created in 1996 by Joss Whedon to produce Buffy the Vampire Slayer. The company also produced the Buffy spin-off, Angel, and his two short-lived science fiction series, the space western Firefly and his high-concept Dollhouse, produced by20th Century Fox Television and Mutant Enemy. Mutant Enemy also produced Dr. Horrible's Sing-Along Blog.
Its offices (made out of glass bricks) were on the lot of 20th Century Fox in Los Angeles, previously the home of Chris Carter's Ten Thirteen Productions. According to March 2006's issue of UK magazine The Word, the offices were closed not long after Angel was cancelled.