Watch Liam Payne Perform 'Strip That Down' on 'The Tonight Show'The performance featured backup dancers in a big neon frame and Payne gave a shoutout to the talk show host.
Watch Shawn Mendes Perform 'There's Nothing Holdin' Me Back' on FallonMendes received a standing ovation for the performance.
Watch Niall Horan Try to Write a Song About 'Quickly Clicky Pens'Horan and Jimmy Fallon have fun in the segment 'Instant Song Challenge.'
Niall Horan Peer Pressures Jimmy Fallon into Gangnam Style DanceHoran had some fun at Jimmy Fallon's expense and performed his single "Slow Hands" on The Tonight Show.
Jimmy Fallon Pays Tribute to David Bowie in SNL MonologueIt wasn't funny, but it was awesome.
Watch Harry Styles and Jimmy Fallon's Snappy New SNL PromoThis will be the first time the show has been aired live on the East and West Coast.
Demi Lovato and Jimmy Fallon Play Teen Girls in "Ew!' SketchDemi held her own in the comedy department, practicing kissing on an Ed Sheeran pillow (Fallon's had Mario Lopez's face on it).
Jennifer Lopez Struts Her Stuff in Silly Dance Battle on 'Fallon'Fallon went first, making up a silly dance called, “Skinny Jeans.” Lopez proceeded to show him up with a very J.Lo version of “Washing Machine Spin Cycle.”
Watch Niall Horan Perform 'This Town' on 'The Tonight Show'Horan is the second member of One Direction to play solo on the program. Zayn Malik performed “It’s You,” from 'Mind of Mine' in February.
Neil Diamond and Jimmy Fallon are Bad at 'Password'It was Neil Diamond and Jimmy Fallon versus Natalie Portman and JJ Abrams, and Diamond just kept guessing "salad."
Justin Timberlake Joins Jimmy Fallon at Camp in 'Tonight Show' SkitIn a room surrounded by childhood games of the '90s like Guess Who? and Battleship, the two friends decide to sing a song they heard on the radio earlier that day -- "Ironic" by Alanis Morissette.
Shawn Mendes Pokes Fun of Jimmy Fallon on 'The Tonight Show'Mendes couldn't help calling Fallon a "grandpa" and reminding the host about their age difference.