Jed Whedon

"Dr. Horrible" is about a man who considers himself a villain and is only waiting to receive his official acceptance into a league of villains, though to do that he must succeed at an evil plan or most specifically, kill someone, neither of which he has been able to do. (IMDB Comments)

A three part feature focusing on various parts of the creation of the film. First we focus on the forces in play that helped create the film, from idea to casting and the incorporation of various writer's ideas. Next, the musical elements of the film are dissected and explained, from lyrics creation, to recording. It's worth watching, even if it's very dry. Last up is a general interview and thoughts section, including a rare physical display of kissing one's own ass. (bluray.highdefdigest.com)

Dr. Horrible's Sing-Along Blog commentary track comprising entirely new songs performed by the cast and crew, thus creating a whole other musical on its own. The actors and writers sing various songs both as solos and with the entire company, playing versions of themselves.