On "Glee," Mercedes (Amber Riley), Santana (Rivera) and Brittany (Heather Morris) have left the New Directions to join Shelby Corcoran's (Idina Menzel) all-girl glee club, the Trouble Tones. Here, Rivera talks about collaborating with the girls on the musical milestone and shares the scoop on the upcoming episode.
Here's how Fox describes "Mash-Off": "Sue (Jane Lynch) 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 (Menzel) encourage some friendly competition."
For a full list of the 300 "Glee" performances, click here. To watch the "Rumor Has It" / "Someone Like You" performance click here.
"Glee" airs Tuesday nights on Fox at 8 PM ET.
To check out the "Mash-Off" preview, look below: