Watch Melissa McCarthy lip sync battle Jimmy Fallon

Monday’s episode of Fallon welcomed star of the upcoming movie The Boss and all around funny person Melissa McCarthy. It wasn’t business as usual for the two comedy stars. The two went head to head in a lip sync battle, and it was one for the ages.

The Lip Sync Battle is easily the biggest hit segment in the Fallon era of The Tonight Show. It’s not something that can be done on a weekly basis like Jay Leno’s Headlines, but it pulls in viewers every time he’s able to get an A-lister in studio to do battle on stage. He also doesn’t want to take viewers away from the actual Lip Sync Battle show, of which he’s a producer.

If I had to guess, I would say this is going to be one of the biggest editions of Fallon’s lip sync battle this year. We’ll see how it does on YouTube for the next month, but it’s already over 2 million views and that’s in less than 24 hours. Check out the full clip below and enjoy the hilarity.

Fallon kicked things off, as he always does in his lip sync battles, by singing “Brand New Key” by Melanie. It’s a song from the 70’s that most people would know if they heard it. The chorus is unforgettable. Melissa fired back with “X Gon Give it to Ya” by DMX. That song has been getting a lot of play this year thanks to this lip sync battle and from being the theme song of the smash hit “Bloodpool.” I won’t spoil their second songs, but it Melissa closed the show phenomenally. It didn’t even have to be put up to a vote.

Be sure to check back to Last Night On for recaps of Fallon for the rest of the week. Wednesday’s show welcomes Cameron Diaz and Jon Favreau.