Colbert squeezed in among the Brady Bunch-style boxes with stars like Sia, Connie Britton and Alan Cumming and sang the Chili's baby back ribs jingle. The Late Show host also performed some impressive ventriloquism and gave a random didgeridoo solo for good measure.
Oliver, meanwhile, injected "Our Fight Song" with his classic British cantankerousness, demanding to know how he'd been duped into appearing in the video. "No one mentioned this was part of a weirdly earnest a cappella song for Clinton," he complained. "Awful!"
At the end of the clip, Oliver expressed his discontent once more, parting a giant Sia wig and cracking, "Again I did not agree to be part of this, this song is going to irritate people."