Screen capture of Santana (Naya Rivera) performing during Glee's 300th musical performance. The episode airs on Tuesday. (PHOTO: 20th Century Fox)

The cast of Glee does it right for its 300th musical performance, borrowing two songs from Adele in an unbelievable mash-up.

In the ladies-only performance, led by Santana (Naya Rivera) and Mercedes (Amber Riley) belt out Adele's Someone Like You and Rumour Has It, backed up by the rest of cast, dressed in black.

The performance has already been approved by Adele herself. On Thursday, the singer's Twitter account re-tweeted a post by @GleeTheMusic, sharing the music video with her fans.

The 21-year-old British singer is currently recovering from throat surgery and is expected to rest through the New Year.

Already in its third season, Glee has been one of the hottest shows on Fox. What's even more impressive is the show's iTunes sales. Since season one's well-received rendition of Journey's Don't Stop Believin', Glee has sold more than 36 million songs on iTunes and more than 11 million albums worldwide.

In February, the show topped Elvis Presley for most Hot 100 hits, according to Billboard.

This season, the Glee kids have done West Side Story while Sue Sylvester continues her run for congress. Most recently, the show was under fire for its First Time episode, with the Parents Television Council calling the network reckless for celebrating teen sex, ABC News reported earlier this week.

From a Britney Spears-themed episode (led by McKinley High's very own Brittany Pierce), to a Lady Gaga inspired episode, to a Madonna tribute, Glee has come a long way to arrive at 300.

And let's not forget the slew of guests that have appeared on the show, including Gwyneth Paltrow, Kristin Chenoweth, Neil Patrick Harris and Idina Menzel.

Scroll down for the music video for the Glee gals singing an Adele mash-up for the show's 300th musical performance.

The episode airs on Tuesday.

Which artists should the Glee cast cover for its future episodes? Share your thoughts below.