Overseas Glee mania!

Proving their worth across the pond, the cast of Fox's Glee offered up a live version of Journey's "Don't Stop Believin,'" on Sunday's X-Factor.

Performing as their characters during the British show's semi-final round, the cast belted out the tune as seen on the "Sectionals" episode. (Watch a clip above)

An added bonus for British viewers? Riley even serenaded show judge Simon Cowell!

Cast member Chris Colfer was noticeably absent for the weekend performance, but with good reason.

"I had to stay and film scenes with the Warblers. Lot's of cool stuff coming up!" the actor Twittered Friday. "I expect my costars to bring me back enough "William & Kate" merchandise to fill a small house."

Colfer will, however, join his costars for a series of live stage shows in Europe next summer.

WANT MORE GLEE? Check out Us' Glee! The Complete Guide, available at Barnes & Noble today!

Hitting cities including London, Dublin and Manchester, the GLEE LIVE! tour -- featuring popular routines seen on the show -- will be staged from June 22-July 3.

Glee airs Tuesdays at 8 p.m. (EST) on Fox.