Isaac, Taylor and Zac Hanson are famous for their flawless harmonies and catchy, pop-rock tunes, so it’s no wonder they befriended cast members of FOX’s musical sitcom, ‘Glee.’ The brothers hung out with Matthew Morrison and Darren Criss last weekend, and there are tweets and pictures to prove it!

Yesterday (April 7), Taylor tweeted an Instagram photo from a hang session with Morrison, who was recently recruited by Adam Levine to record a duet.

Then, late last night, Hanson launched a surprise live video stream on their website and played a couple of songs from their forthcoming album, ‘ANTHEM.’ During their performance of the disc’s lead single, ‘Get the Girl Back,’ Criss joined them onstage to add his smooth vocals to the tune.

Criss also took to Twitter and expressed his excitement about crashing Hanson's rehearsal:

 

At the end of the video stream, Taylor named Criss “the new fourth Hanson,” which left us dying to know if we can expect a Hanson + ‘Glee’ collaboration in the future. In the meantime, be sure to tune in to 'The Tonight Show With Jay Leno' tomorrow night (April 9) to watch the talented trio perform their new single!

Watch Darren Criss Perform With Hanson