Darren Criss (b. 1987) is an American actor best known for his role as Blaine Anderson on Glee.
The appearance at the Hollywood Roosevelt Hotel was hosted by Ross Mathews. Criss and Kermit, both in tuxedos, sang "Rainbow Connection," with Criss on guitar. Afterwards, the Glee star invited Kermit to come on his show, to which the frog invited Criss to appear in the next Muppet movie.
Criss' other credits include playing Harry Potter in the spoof A Very Potter Musical, and the Broadway musical How to Succeed in Business Without Really Trying, replacing Daniel Radcliffe (who incidentally portrayed Harry Potter in film).