I feel like this isn't very good... But there'll probably be more and hopefully it will get better. Anyway... The basic premise is that Dr. Horrible is the fifth doppleganger. Let me know what you think. Also, this will be posted on multiple spots.
"The Magician's Code" (Parts 1 and 2), the Season 7 finale episode of "How I Met Your Mother," took the viewer on a little tour, and Barney (Neil Patrick Harris) makes the tour magical.