Glee preview: "Mash Off"

When we heard this week's new episode of Glee, "Mash Off," was going to mark the show's 300th musical performance with an Adele mash-up, we were beyond giddy with, well, glee.

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In "Mash Off," Shelby's all-girl group The Troubletones and the New Directions go voice-to-voice in a mash-off to see who's top dog.

The Troubletones, which includes Mercedes (Amber Riley), Brittany and Santana, (Naya Rivera), are taking on a mash-up of Adele's "Rumour Has It" and "Someone Like You."

Check out a preview of "Mash Off" and then head over to Fox to catch the full episode Tuesday night (Nov. 15)...

Fox officially describes "Mash Off" as the following: "Sue starts a smear campaign to take down her biggest competitor for the Congressional seat. Meanwhile, Puck (Mark Salling) has a crush, and Will (Matthew Morrison) and Shelby Corcoran (guest star Idina Menzel) encourage some friendly competition."

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Puck has always had a thing for older ladies and his new feelings for Shelby are bound to get messy for two reasons -- one, Shelby's raising his daughter, and two, Quinn wants Shelby to hand Beth back over.

Baby Beth's adoption is coming full circle -- but the chances of Ryan Murphy putting Puck and Shelby together are slim.

We want to hear from you -- now that winter is upon us and Glee will soon be leaving us for a small break, what do you want to see happen?

Head over to our comments section and sound off!

Photo courtesy of Fox