Cory Monteith, best known for his role as Finn, on the hit series "Glee," has exited ongoing production and has checked himself into rehab for substance abuse addiction.

"Cory is a beloved member of the Glee family and we fully support his decision to seek treatment,” a spokesman for FOX said in a statement. “Everyone at the show wishes him well and looks forward to his return.”

While this comes as a shock, Monteith has opened up about addiction related troubles in recent years, admitting that he had checked into a rehab facility when he was 19.

It's unclear if his exit will have a major effect on the currently in production fourth season of "Glee." It's also unclear when or if Cory will return to "Glee."