Justin Timberlake And Jimmy Fallon Can’t Keep It Together For An ‘Ironic’ Sing-Along

Justin Timberlake and Jimmy Fallon laughed their way through a summer camp sketch and sang Alanis Morissette's 'Ironic' on 'The Tonight Show'

Ashton Kutcher Pulled A SpongeBob And Ripped His Pants On National TV

Ashton Kutcher guest-starred on 'The Tonight Show' and accidentally ripped the crotch of his pants.

Shawn Mendes Parodies Justin Bieber With A Song About Hiding His Bong

Shawn Mendes plays the Hashtag Game on 'The Tonight Show,' parodying songs by Adele, Coldplay, and, most hilariously, Justin Bieber.

Miley Cyrus Gives Off Hannah Montana Vibes During ‘Ew!’ On The Tonight Show

Miley Cyrus throws it all the way back to her 'Hannah Montana' days while stopping by Jimmy Fallon's 'The Tonight Show.'

Stranger Things’ Mike And Eleven Had Very Different Reactions To Their Big Kissing Scene

The 'Stranger Things' kids stopped by 'The Tonight Show,' talking about Eleven's kissing scene, playing a silly string game, and acting in a new scene with 'Barb.'

Miles Teller Is Telling That Incredible Shark Story (You Know The One) Again

Miles Tellers tells Jimmy Fallon how he saved a pregnant woman and her toddler from a shark.

Jonah Hill Sent His Food Diary To Drake And Things Got Awkward

Jonah Hill tells Jimmy Fallon how he accidentally emailed his food diary to Drake.

Ariana Grande Made A New 'Into You' Video With Every Single Snapchat Filter

Ariana Grande made another video for 'Into You' with some help from Jimmy Fallon and Snapchat.

Watch Kristen Stewart Take Jell-O Shots Like A Champ While Playing Twister

Jimmy Fallon challenged Kristen Stewart to a Jell-O Shot Twister game on Monday's 'Tonight Show.'

About That Time Nick Jonas Popped A Boner On The Red Carpet

Marijuana can have some weird side effects, especially if you're a Jonas brother.

Watch President Obama Sing Along To Rihanna's 'Work' — Yes, Really

President Barack Obama slow jammed the news on 'The Tonight Show Starring Jimmy Fallon.'

Daniel Radcliffe Was A 'Stern Old Lady' In A Past Life

Jimmy Fallon introduced Daniel Radcliffe to his doppelgängers on "The Tonight Show."

Karlie Kloss Tried To Teach Jimmy Fallon How To Pose Like A Supermodel

Almost, Jimmy

Watch An iCarly Star Make A Sex Joke And Promptly Ruin Your Childhood

Jerry Trainor from Nickelodeon's "iCarly" and "Drake & Josh" made a raunchy joke on "The Tonight Show Starring Jimmy Fallon."

The Lonely Island's G-Rated 'I'm On A Boat' Is Even Funnier Than The Original

The Lonely Island teamed up with The Roots to perform 'I'm on a Boat' with toy instruments.

Watch Meghan Trainor Fall Down — And Stay Down — On Stage

Meghan Trainor's heel betrayed her during her "Me Too" performance on "The Tonight Show Starring Jimmy Fallon."

Watch Ariana Grande And Jimmy Fallon Lip-Synch An Entire Conversation

Ariana Grande and Jimmy Fallon figured out a way to speak to each other by lip syncing the hits.

Ellie Kemper Told Tina Fey She Was Pregnant Before She Told Her Own Mother

'Unbreakable Kimmy Schmidt' star Ellie Kemper revealed on 'The Tonight Show' that she was pregnant.

Jimmy Fallon's David Bowie Impression Is 100 Percent Serious

Backed up by Chris Martin, Jimmy Fallon honored David Bowie with a solemn cover of 'Life On Mars?'

Jake Gyllenhaal Straight Up Bombed His Lord Of The Rings Audition

Jake Gyllenhaal completely bombed his Frodo audition for "Lord of the Rings."

Beyoncé And Bruno Mars Secretly Challenged Chris Martin To A Dance-Off At The Super Bowl

Beyoncé and Bruno Mars convinced Chris Martin to compete in a dance-off during their Super Bowl 50 halftime show.

Zayn Hits All The High Notes On Swoon-Worthy New Song ‘It’s You'

Zayn Malik premiered new song "It's You" on The Tonight Show Starring Jimmy Fallon and revealed his solo album's cover art.

Watch Jimmy Fallon And Natalie Portman Become Sia To Sing With Sia

Sia, Natalie Portman, The Roots and Jimmy Fallon remake "Iko Iko."

Rashida Jones And Jimmy Fallon Transformed Taylor Swift, Drake And Rihanna Into Holiday Songs

Rashida Jones and Jimmy Fallon honored their annual tradition of transforming the year's most popular songs into holiday themes.