Angel

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4. "Angel" (Spun off from "Buffy the Vampire Slayer") No, we’re not crazy enough to say that "Angel" was better than "Buffy" overall, but Angel’s darkest moments during his show’s second and third seasons, which included the return of Darla and Wesley’s betrayal, were more compelling than the annoying Dawn/Glory and resurrection storylines in the fifth and sixth seasons of "Buffy."

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Click on the link for more :

http://tv.yahoo.com/blog/ten-tv-spinoffs-that-were-better-than-the-original-shows—664