"Monsters University" cast attends blue carpet premiere Class is now in session at "Monsters University." The voice cast from Disney/Pixar's newest 3D animated offering attended the blue carpet premiere Monday in Hollywood, Calif. "Monsters University" premieres in Hollywood Celebrities like Gwen Stefani and husband, Gavin Rossdale, brought their kids to the family-themed event complete with a tailgating party, cheerleaders and a large marching band in celebration of the film's collegiate theme. "Monsters University" serves as a prequel to the 2001 hit, "Monsters Inc." Billy Crystal and John Goodman return to lend their voices as the creatures Mike and Sulley, who must learn to get along and pass Scaring 101 during their first semester on campus. "Cheers" star John Ratzenberger also returns for the sequel, but he's playing a different character this time around. In the first film, he voiced the role of the Abominable Snowman. Now, he's portraying a yeti, which he seems to know a thing or two about. "I used to be a yeti," Ratzenberger joked at the premiere. Well I lived with a tribe of yetis. I was captured. I was forced to marry the yeti princess. Watch video above to see Crystal and Ratzenberger on the blue carpet. "Monsters University" opens in theaters on Friday.