When Santana comes home to Lima on this week's "Diva" episode of Glee, she's in for a bit of a rude awakening.

After a detour to New York from her home in Kentucky, where she's (unhappily) attending the University of Louisville on a cheerleading scholarship, Santana will visit McKinley High, where she'll find her ex, Brittany (Heather Morris), has already moved on -- with Sam.

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This being Diva Week for New Directions, Santana (Naya Rivera) and Sam (Chord Overstreet) will share a duet -- with very different personal meanings for each of them -- when they cover "Make No Mistake (She's Mine)" by Kim Carnes and Barbara Streisand.

Will seeing the new couple be the ammo Santana needs to finally head to New York for good? "There has to be some catalyst back at McKinley that really would have her realize there's nothing left there for her," Rivera recently told The Hollywood Reporter, noting Santana won't like what she sees when she comes home during the "Diva" hour. "In that episode, everything gets wrapped up. One door is closing for her, and she opens another one. It's a good thing -- she's growing."

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Morris, meanwhile, seemed to indicate Sam and Brittany will withstand Santana's visit. "I don't think they were great for each other, even though they're best friends. Sam gives her more room to just be herself, and that's a lot of fun," the actress recently told THR.

Check out the song, above, and hit the comments with your thoughts on how Santana will respond to seeing Sam and Brittany together. Glee airs Thursdays at 9 p.m. on Fox. For more music from Glee, head to GleeTheMusic.com.

Email: Lesley.Goldberg@thr.com; Twitter:@Snoodit