Stephen Colbert Mocks 'Today's' On-Air Prostate Exams (Video)

The host is joined by John Lithgow, Katie Couric and The Black Keys for an over-the-top medical segment.

Among those inspired by Matt Lauer and Al Roker's on-air prostate exams during last week's Today show was Stephen Colbert's late-night host character, who saw an opportunity to out-do Today with a star-studded, over-the-top on-air exam.

"I will not be out-sweep-swept by the Today show," Colbert said of their segment.

"It's no accident that they pulled this ground-breaking stunt during November sweeps because the Today show knows what brings in the great ratings: Men in their 50s, being finger-puppeted," he added.

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But he noted that sweeps are really all about the guest stars and brought out John Lithgow, Katie Couric and The Black Keys, who were all there to examine his prostate in a segment he called "Stephen Colbert's November Sweeps Prostacular."

But, only one of these guest stars could do the honors.

"Due to limited capacity in my colon, I can't fit you all in there," he explained. "I'm going to have to make a choice in tonight's highly dramatic latex glove ceremony."

Colbert then revealed a glove on a silver platter that he held while Lithgow, Couric and the Keys made their pitches.

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Couric talked about her on-air colonoscopy to demonstrate her "commitment and experience," and noted that she "just got a manicure."

And the Black Keys said that Colbert should think of them as "The Brown Keys," with the band's frontman performing the exam.

But, Lithgow won with this creative argument: "As star of Harry and the Hendersons, I've stood face to face with a Sasquatch, so whatever you've got going on down there won't frighten me."

Couric then had a mock reality TV contestant freak out, calling Lithgow a "bitch" and saying, "he's not even here for the right reasons," before storming off.

Colbert's exam lasted just 24 seconds, 10 seconds shorter than Lauer and Roker's exams, when Lithgow stopped after he found kittens, lifting two small cats over the privacy screen.

But the Comedy Central host teased another prostate exam during February sweeps week, in Hawaii, before showing a graphic of himself, Lithgow and the Black Keys surfing, with Colbert still partly covered by a curtain.