10 Buffy The Vampire Slayer Actors Who Went On To Star In Supernatural

The German-born, American-raised Harry Groener may be less of a big name than some on this list, having spent more of his career doing stage work and walk-on parts for TV, but that doesn't diminish an ounce of his sizeable powers.

Perhaps the most quirky and charismatic Buffy villain of all, it is difficult not to be taken in by the small-town quaintness of season three's Big Bad, Mayor Richard Wilkins III. Groener brought depth and complexity to the role, which he held throughout season three and reprised several times in later seasons, presenting us with a villain who couldn't tolerant germs or bad language on the one hand, and stuffed his face with giant demonic spiders with the other.

Tapping into the homeliness and charm that ensnared us all the first time around, Groener played Professor Morrison in a couple of episodes of Supernatural. A university lecturer in anthropology, Professor Morrison occupies a Giles-esque role for the Winchester brothers, acting as one of their go-to experts and helping them decode ancient languages and symbols.

While the former may have been Groener's career-defining part, perhaps never to be surpassed, that hasn't stopped him popping up all over the place, including on Modern Family and Young Sheldon in recent years.