Lea Michele, Chris Colfer, Cory Monteith Leaving Glee After Season 3

  Jason Merritt/Getty Images; Stefanie Keenan/WireImage.com; Toby Canham/Getty Images

At the end of Glee's third season, Lea Michele, Chris Colfer and Cory Monteith will be out work. According to series co-creator Ryan Murphy, the three regulars will not "be back at all for Season 4."

"You can keep them on the show for six years and people will criticize you for not being realistic," Murphy tells The Hollywood Reporter, "or you can be really true to life and say when they started the show they were very clearly sophomores and they should graduate at the end of their senior year."

Michele, 24, and Colfer, 21, are on-board with Murphy's decision to write their characters off the show. "I involved Chris and Lea and they thought that was a good idea," he says. "They both trust the writing and trust me and felt that it would be great to have an open and closed experience for them to go out while they were on top."

"I'm much more interested in Lea's character — not so much on her relationship with Finn, but more on what her dreams are beyond high school and how she plans on getting them," he adds. "That's what my senior year was about."

Murphy has yet to discuss the casting changes with Monteith, 29, but he doesn't think the actor will be too shocked by the news. "He knows he was a sophomore when the show started," Murphy explains.

Though he won't reveal the rest of the cast's fate until the Sept. 20 premiere, Murphy warns: "More characters are leaving than are staying."

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