Jimmy Fallon Reveals the 'New Era' of 'The Tonight Show' to Brian Williams (Video)

Brian Williams With Jimmy Fallon - H 2014

Brian Williams With Jimmy Fallon - H 2014

UPDATED: The excited new host revealed that it is "all starting to sink in," when he sat down with the NBC anchor and gave him a private tour of the studio, complete with a "urinal" and a "hot tub."

As viewers anxiously anticipated his debut on The Tonight Show, Jimmy Fallon sat down with NBC Nightly News host Brian Williams to reveal what to expect when he takes the hot seat.

From the highly anticipated guest list to his previously unseen new studio, Fallon and the news anchor had fun amping up the excitement for his first show on Monday night since taking over from Jay Leno.

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"It is all starting to sink in and it's real, this is going to happen," Fallon told Williams just hours before the first episode aired. 

With The Tonight Show filming in the Big Apple just down the hall from Fallon's Late Show studio, the host revealed why the location is so important to the soul of the series. 

"It is where The Tonight Show started -- actually in the studio where we are going to be, that's where Johnny Carson was, there's Broadway, there's Times Square, there's something glamorous about it. That is The Tonight Show," he gushed.

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House band The Roots have created a new theme song, which Jimmy debuted on NBC Nightly News "from his iPhone into his microphone with live narration," explained Williams, as Fallon grooved to the tune and belted out sound bites.

The news anchor went on to praise the former SNL cast member, and credited him for having "modernized late night comedy. Jimmy Fallon has been built to please. He works for his laughs," said the NBC veteran.

Fitting for the theme of the new generation of talk shows, the pair ended on a funny note with a secret tour of The Tonight Show set, which has been kept heavily under wraps.

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"While our cameras were not allowed in because the network didn't want to spoil tonight's debut, it is hard to adequately describe what we saw.

"I can't believe you have done all this in pink," said Williams, from behind closed doors. 

"Pink is the new blue," explained Fallon, before Williams asked: "And why the urinal?"

"Just efficiency…maybe the hot tub is too much. I am keeping the urinal," vowed the host. "Are you sure this is going to be ready for tonight?" asked Williams. "It better be -- we are going on the air," replied Fallon.

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Whether there really is a hot tub and urinal remains to be seen, but the new studio will no doubt be flawless when The Tonight Show welcomes first guests Will Smith and U2.

The Tonight Show Starring Jimmy Fallon launches following the Sochi Olympics at midnight, Feb. 17-20, with the Feb. 21 telecast to air in its regular 11:35 p.m. ET/PT time slot. The show is relocating to New York and will tape before a live audience from the renovated Studio 6B in Rockefeller Center.

Wearing a light grey suit, white shirt and skinny navy tie, Fallon told his audience at 30 Rock's newly redesigned Studio 6-B (the original Tonight Show studio before Johnny Carson took the show to Burbank in 1972) that his goal is to "put a smile on your face." But he also assured that, contrary to his good-boy image, he will "make fun of everybody. Anyone I can make fun of, I will."

With that, he acknowledged the aforementioned onetime elephant in the room: "Welcome to The Tonight Show. I'm Jimmy Fallon and I'll be your host -- for now." He continued: "Of course I wouldn't be here tonight if it weren't for the previous Tonight Show hosts, so I want to say thank you to Steve Allen, Jack Parr, Johnny Carson, Jay Leno, Conan O'Brien and Jay Leno."

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There was a mid-show performance by U2 at the Top of the Rock, the observation deck 70 stories above Manhattan that boasts gorgeous panoramic views of the city. The band performed their new single "Invisible" against the late-evening backdrop. Apparently, the sunset was ordered up by executive producer and late-night impresario Lorne Michaels -- sort of. It was Michaels' idea to have the band perform in the middle of the show (rather than at the end, which is standard) in order to take advantage of a brilliant sunset that left an fiery orange streak across Manhattan's iconic skyline, with the spire of the Empire State Building illuminated in red, white and blue. U2 returned to close the show with an impromptu acoustic rendition -- on the Tonight Show sofa -- of "Ordinary Love," their Oscar-nominated single from Mandela: Long Walk to Freedom.

But the highlight of the show for late-night fans will likely be an early segment that stands among the most impressive booking coups in television. As Fallon primed the audience for Smith and U2 ("Their musical performance is going to blow your pants off," he promised), he added, seemingly as an aside, "I can't believe this is happening. I want to say thanks to all the fans for all of their support. And to my buddy who said that I'd never be the host of The Tonight Show -- and you know who you are -- you owe me a hundred bucks."

With that, Robert DeNiro walked out from backstage and without a word slapped a $100 bill on Fallon's desk. He was followed by Tina Fey, Joe Namath, former New York mayor Rudy Giuliani (who thanked Fallon for "bringing it back to New York"), Mariah Carey (who pulled $100 from deep within her cleavage, encased in a black evening gown), Joan Rivers, Kim Kardashian, Seth Rogen, Mike Tyson, Lady Gaga (wearing a black fishnet body stocking and little else), Lindsay Lohan, Tracy Morgan, Sarah Jessica Parker (who was carrying the $100 in her right stiletto) and finally, Stephen Colbert. The Colbert Report host dumped a bucket of pennies on Fallon. He then pulled out his iPhone to snap a selfie of the two of them before declaring: "Welcome to 11:30, bitch!"

Marisa Guthrie contributed to this report