Jimmy Fallon does Bill Cosby impression and gets carried away — by Cosby

Image: Jimmy Fallon and Bill Cosby
Nathaniel Chadwick/NBC

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By Ree Hines

"Tonight Show" host Jimmy Fallon is a master mimic, and he proved that once again Wednesday night when he delivered his very best impersonation of beloved funnyman Bill Cosby — right in front of beloved funnyman Bill Cosby.

"I can't help but talk like you when I talk to you," Fallon told his guest. "'Cause when I talk to you ... I ... slow ... ev-ery-thing ... down."

From there, Fallon went into the full Cos, complete with a "Cosby Show"-worthy dance, while the venerable actor turned his back and did universal sign for "cut" by running his finger across his neck. Cosby then walked away.

"Bill, don't leave," Fallon begged. "Don't be upset."

Of course, Cosby was far from upset. He was just doing his signature deadpan disapproval. But that's not all he did. In honor of Fallon's extreme-sports theme night, the 76-year-old also did a tightrope routine during is "Tonight Show" stop.

Well, sort of. What Cosby actually did was grab a pole and walk a wide line across the stage with a nod to tightrope daredevils such as Nik Wallenda, who once walked over Niagara Falls.

"I don't understand why in life, with all the jobs people do, you would want to now have the Falls beneath you," Cosby said as he started his demonstration.

But it was a short demo. Just two steps into his effort, he stepped right off the line. That's when Fallon decided to lend him a hand by jumping on Cosby's back. The comedian carried Fallon all the way to the end of the segment.

"The Tonight Show" airs weeknights at 11:35 on NBC.