Darren Criss, Dianna Agron and Glee Cast Join YouTube Sensation Keenan Cahill for 'Don't Stop Believin''

Illinois teenager Keenan Cahill couldn't have possibly imagined some of the music industry's biggest stars would join him for sing-alongs when he began posting videos on his YouTube page last year. Cahill became a surprise Internet sensation, performing with the likes of 50 Cent and Katy Perry, and now the cast of Glee has joined him for some viral fun. Lip-synching to one of the show's signature songs, Journey's "Don't Stop Believin'," Darren Criss, Dianna Agron, Harry Shum Jr. and Jenna Ushkowitz took to back-up duty for Cahill as he channeled both Lea Michele and Cory Monteith. Think there's a spot available at New Directions for Cahill? Take a look below!