"Glee" is about to get a good, old-fashioned dose of vampire.
Whedon is responsible for one of the most memorable episodes of "Buffy," featuring the cast members in a musical episode titled "Once More, With Feeling" that became a cult phenomenon. He's also the mastermind behind "Dr. Horrible's Sing-Along Blog."
Twentieth Century Fox approached Whedon, a known musical theater fan, about directing an episode of the series -- and Whedon was thrilled to comply, "Glee" creator Ryan Murphy said.
"Joss directed on eof the great musical episodes in the history of television on 'Buffy,'" Murphy said. "So this is a great, if unexpected, fit. I'm thrilled he'll be loaning us his fantastic groundbreaking talent," he said.
Whedon is currently at work on the series "Dollhouse," starring Eliza Dushku.
"Glee" fans will also be treated to the musical stylings of "Spring Awakening" alum Jonathan Groff, who Entertainment Weekly reported Monday has signed on to star in five or six episodes of the series. He'll serve as a potential love interest for Rachel, played on the show by his former "Spring Awakening" co-star Lea Michele.
"Glee," which stars comedian Jane Lynch and Broadway stars Michele and Matthew Morrison, airs Wednesdays at 9 p.m. on Fox.