The network confirmed to Access Hollywood on Wednesday that the singer-actress is joining the show's cast for its upcoming third season. She's set to debut in the fourth episode on October 5.

LOS ANGELES, Calif. -- With his breakout role in the charming and very funny new comedy "17 Again," teen idol Zac Efron is basically sending a not-so-subtle message to anyone in Hollywood who will listen: bye-bye "High School Musical," hello movie career.

Otherwise, "17 Again" could best be described as a hodge-podge of past "what if" films, like "Big," "13 Going on 30," the similarly-titled "18 Again" and both versions of "Freaky Friday." But it's still a good movie, thanks to a charming screenplay by Jason Filardi ("Bringing Down the House"), vibrant direction from Burr Steers ("Igby Goes Down") and a star-making performance by Efron.

"This is actually the first time I've said those words," she told Access' Tony Potts at the Sundance Film Festival, where she was promoting the drama "Against The Current."

LOS ANGELES, Calif. -- With the Sundance Film Festival, the Oscar nominations and the presidential inauguration, find out where the stars celebrated this week.

Zac's celebration started at LA's Pace restaurant with guests that reportedly included his family, girlfriend Vanessa Hudgens, and "HSM" co-stars Ashley Tisdale and Monique Coleman, People reported.