Robert De Niro, Fallon's very first guest, played up his tough-guy shtick while Fallon lobbed him "questions with one-word answers." Then the veteran actor tried to stoke the funny with a Conan-esque creative skit called "Space Train."
Justin Timberlake also stopped by for the opening night. The singer, who has boosted his comedy chops with regular appearances on "SNL", kept it real with a bit of song-and-dance, and an over the top impersonation of John Mayer.
Guests with the caliber of De Niro and Timberlake may not come all that often (in fact, an opening skit between Fallon and outgoing host Conan O'Brien, who was there cleaning out his dressing room, eluded to that point specifically), but it's not the guests that critics will be judging over the next few days. They're going to rate Fallon.
For his part, Fallon started well by paying homage to his predecessors. Not only did "Space Train" feel like classic Conan, but Fallon set up what look they'll be recurring gags along the lines of the Stupid Human Tricks, ala-David Letterman, who had the show before O'Brien took over more than a decade ago.
"Licking for $10" is a game that requires audience members to lick various objects for a chance to win $10. Monday night's objects included a lawn-mower, a copy machine and a goldfish bowl.
Another feature that should become a recurring theme on the "Late Night" is called "Slow Jamming the News", and it puts the house-band The Roots to good use.
Fallon, who is a former cast member of "Saturday Night Live" with several films to his credit, has tapped a longtime "SNL" hand, Michael Shoemaker, to be his producer. Co-producer is Gavin Purcell, who ran "Attack of the Show," the daily Net-centric news hour on cable's G4 channel.
Lorne Michaels (who used to be Fallon's boss on "SNL") continues as "Late Night" executive producer.
Reviews of the show should be forthcoming, but glimpses of the Fallon-era "Late Night" have been shared with viewers in the form of "video blogs" on the show's Web site for weeks.
"I know I'm gonna get reviewed off the first show, as opposed to the first couple of months," Fallon predicted in a recent interview. "'He's no Conan,' or 'He's no Letterman' — I just want that to be said, and put out there. Then viewers can relax and watch and enjoy."
Fallon's on-air arrival sets in motion a carefully arranged host shift by NBC. O'Brien, who took over "Late Night" from its original host, Letterman, in 1993, is now devoting full time to readying his version of the Los Angeles-based "Tonight Show," where he will land in June.
"Tonight Show" veteran Jay Leno will return to the air come Fall with a weeknight prime-time talk-variety show airing at 10 p.m.