No sweater needed! Jimmy Fallon proved he is still owning late night TV when he invited seasoned comedian Bill Cosby onto The Tonight Show on Wednesday, March 26. 

Before Cosby, 76, even had a chance to sit down or speak, Fallon, 39, quickly jumped in with his best impersonation of the famed sitcom star. 

"Bill, I can't help but talk like you when I talk to you," he started in a spot-on imitation of Cosby's iconic laid-back voice. "Cause when I talk like you, I slow everything down. And start to talk like you. And I dance like you, and I do the moves like Bill Cosby does the dance moves." 

Showing off some of the quirky dance moves from The Cosby Show's classic opening montages, Fallon caused the star to shake his head no before walking away from the guest chairs.  

"Bill, don't leave, now don't be upset, please!" Fallon called after him. 

The SNL alum managed to keep Cosby in the studio, even convincing him to do a "grounded" tight rope walk. After one of TV's favorite fathers complained about tightrope walkers in general, Fallon hopped on Cosby's back, clinging to his head as they walked across the studio. 

"You know I have this pole?" Cosby quipped to Fallon after the host poked fun at him. "Hey man, don't make me mad!"