Exclusive: Glee to Air Super-Sized [Spoiler]-Themed Episode on May 15

Fox is turning Glee‘s third trip to Nationals into an all-night event.

Sources confirm to TVLine exclusively that the network is combining the show’s 20th and 21st installments into one, two-hour episode on Tuesday, May 15.

But it’s the first of those two hours — which finds New Directions planning for the annual competition — that is likely to generate the most watercooler chatter. That’s because in the midst of rehearsing their new routine, Tina (Jenna Ushkowitz) suffers a mild head injury and begins to experience a different — yet oddly familiar — alternate reality.

The plot would seem to give context to recent photos from the set showing the cast swapping roles — i.e. Mark Salling (Puck) playing Blaine, Cory Monteith (Finn) dressed up as Kurt, and the aforementioned Ushkowitz channeling Rachel.

Tina’s warped perspective presumably returns to normal in time for Nationals, which serves as the focus of Hour 2.

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