Set in a world where the concept of lying doesn't exist, a loser changes his lot when he invents lying and uses it to get ahead.

Aspiring super-villain Dr. Horrible wants to join the Evil League of Evil and win the girl of his dreams, but his nemesis, Captain Hammer, stops him at every turn.

The cast and crew of Dr. Horrible's Sing-Along Blog (2008) perform a "most uncommon" musical commentary track for the show, acting as exaggerated versions of themselves. After reviewing the circumstances that led to the creation of Doctor Horrible, the characters sing of the contrary and cheap Joss Whedon, the aspirations of the minor actors, the egos of Nathan Fillion and Neil Patrick Harris, and everyone's favorite iPhone game.