'Glee' hit No. 1 on iTunes for the second time this season with its rendition of the fun. track 'We Are Young,' which was featured on Tuesday's 'Hold on to Sixteen' episode.

The anthemic cover was performed on the show by both New Directions and the Troubletones uniting the two show choirs with its lyrics and powerful chorus. The song, which features Janelle Monae, is the lead single from fun.'s sophomore album, 'Some Nights,' due out in February.

When the band was approached with the opportunity, they didn't hesitate to be involved. "I was like, 'Yeah, do it for sure,'" frontman Nate Ruess tells Entertainment Weekly. "We all feel like 'Glee' is such a progressive show. We are insane musical theater fans. It could be the smallest show in the world, but because of a lot of the things it stands for and the message it sends, we had no apprehension about it."

After the cover's debut on the hit FOX series, it quickly shot to the top of the iTunes chart. This is the second No. 1 for the show this season, following the chart-topping Adele mash-up 'Rumour Has It/ Someone Like You' from the 'Mash Off' episode.

Listen to the 'Glee' Cast Sing 'We Are Young'