Moynihan frequently performed with the
Derrick Comedy sketch group and appeared in many of their popular internet videos and various projects. He also filmed a supporting role in the group's feature film
Mystery Team, which premiered at the
Sundance Film Festival in 2009 before a limited theatrical release. In mid-2008, Moynihan had a supporting role in the popular web-series
The Line, an online video project funded by
Lorne Michaels' production company, directed by
SNL head writer and cast member
Seth Meyers, and starring
SNL cast members
Bill Hader and
Jason Sudeikis. He acted as a sketch regular on ''
Late Night with Conan O'Brien'' for a number of years and was a contributing writer on MTV's
Human Giant, and in years past, he often submitted scripts to
SNL with comedy partner
Charlie Sanders. Moynihan has also acted in a number of comedy shorts for the website
CollegeHumor, including their webseries
Every Week on Entourage where he plays "Turtle" from
Entourage. During the summer of 2008, Moynihan featured in a national television ad campaign for
ESPN Radio with Yankees broadcaster
Michael Kay. In the summer of 2009, Moynihan starred in the music video for
Colbie Caillat's single, "
Fallin' for You". He also appeared in three of The Lonely Island's music videos; "Boombox", "Shy Ronnie 2" and "Threw It On The Ground". He made a guest appearance as the drug-addicted Conrad Bellingham on
Mercy. He also appeared in the films
The Invention of Lying,
When in Rome, and
Certainty. In 2013, he made his voice acting film debut in
Monsters University as Chet Alexander, a member of the Roar Omega Roar fraternity. Moynihan also voiced the titular character in the
FX animated comedy
Chozen, which aired for one season in 2014. In 2015, he was a featured character, Lenny, in the romantic comedy film
Slow Learners (original title
Bad Boys, Crazy Girls). He also voiced Panda in the
Cartoon Network series
We Bare Bears, as well as Hal the Dog in the
PBS Kids animated series
Nature Cat. In 2016, Moynihan appeared in a commercial for
Pizza Hut's Bacon
Stuffed crust pizza, and voiced Mel from
The Secret Life of Pets in the same year. After
SNL, he was the lead in the short-lived
CBS sitcom
Me, Myself & I. From 2017 to 2021, he voiced the character
Louie Duck in the
Disney Channel/
Disney XD revival of
DuckTales. In June 2023, he started voicing the character Bobby Boots in the
Disney Junior TV series
Pupstruction. From 2021 to 2022, Moynihan played interim Director of Communications Jayden Kwapis in the
NBC sitcom
Mr. Mayor, and stars as the titular manatee in his series
Loafy. In December 2021, Moynihan wrote the segment "The Holiday Pact" in
DC Comics' anthology special
Tis the Season to Be Freezin', starring the
Flash and
Captain Cold. Moynihan released a children's book titled
Not All Sheep Are Boring, with illustrations by Julie Rowan-Zoch and published by Penguin Random House, in 2022. In March 2025, Moynihan appeared on Season 2 of
Dropout’s interview-parody show
Very Important People in the episode "Dan Wesley Sharron", playing a frozen man with the same name. In
2025, he was unsuccessfully nominated for a
Children's & Family Emmy for Outstanding Voice Performer in a Preschool Program.
Saturday Night Live Moynihan joined the cast of
NBC's
Saturday Night Live during
season 34 on September 13, 2008, and remained through the end of
season 42 on May 20, 2017. He has made subsequent cameo appearances during
Jack Harlow's hosting debut in 2022 and the
Saturday Night Live 50th Anniversary Special.
Recurring characters on SNL • Mark Payne is a waiter at Pizzeria Uno. He wears a T-shirt featuring
Sagara Sanosuke from
Rurouni Kenshin and always complains about inconsequential things around the pizzeria. • Dancing skeleton in the Haunted Elevator sketch featuring Tom Hanks as
David S. Pumpkins. Moynihan co-wrote the sketch and
an animated special that aired on NBC the following year. • Anthony Crispino is an incompetent reporter at
Weekend Update. • Vinny Vedecci Jr. is the son of Italian talk show host Vinny Vedecci. He wants to ask celebrities ridiculous questions, but they cannot understand his broken English, which makes him cry. Vinny Jr. is based on Johnny Caspar Jr., a character in ''
Miller's Crossing''. • Liam is one of the kids in Gilly's elementary school class. It is often implied that he hates his stepfather. • Obnoxious Microphone Guy is an annoying man who attends parties and other events and steals the microphone from the emcee. • Scared Straight Kid, one of the three young trouble-makers (along with
Bill Hader and
Andy Samberg) lectured by convict Lorenzo McIntosh (played by
Kenan Thompson) and McIntosh's fellow inmates including hosts Taylor Swift, Lindsay Lohan, and Betty White. McIntosh usually throws his shoe out of anger, and in later sketches he gives it to him to throw. • Ass Dan, a member of the Kick Spit Underground Rock Festival and winner of the Worst He-Man Impression Contest and the Mud-Eating Contest. Even though the Blake Lively/Rihanna episode established that he died in 2009 at the age of 28 (Ass Dan was born in 1981), he was brought back as one half of the
Thrilla Killa Klownz on the episode hosted by Ryan Phillippe in the music video
"Magical Mysteries" (in which it was stated that Ass Dan "did just die" in the 2010 sketch, making Ass Dan 29 at the time), brought back again for the 2010 Crunkmas Carnival sketch (in which Li'l Blaster established that Ass Dan was dead and finally getting the wake he deserves), and brought back again for the 2011 Easter Festival (in which D.J. Supersoak established that Ass Dan was getting a proper burial), making Ass Dan 30 years old at the time of this death. The 2011 Columbus Day Assblast on the episode hosted by Ben Stiller implied that Ass Dan was still alive, though he almost had a heart attack and still died before he could say that he was going to live forever after the heart attack allegedly passed. On the Bruno Mars episode in October 2012, it's revealed that Ass Dan has an identical twin brother named Butt Dave (also played by Bobby Moynihan). • Keith, a young movie fan who is excited about everything except for the illustrious actor/host that week, notably snubbing
Robert De Niro in favor of
Ben Stiller on the set of
Little Fockers. In Keith's first appearance, he snubbed a hockey player (played by host
Bradley Cooper). • Doug, the mechanic for the Merryville Brothers trolley ride. His character was not named on the first sketch with
Jim Carrey as the third Merryville brother. • Richie, the stage manager from
The Best of Both Worlds who has, on two occasions, been murdered by Julie Andrews and Ice Cube (played by
Helen Mirren and
Kenan Thompson respectively) and by Daniel Radcliffe and Clint Eastwood (also played respectively by Hugh Jackman and
Bill Hader). • Slappy Pappy, one of the regular comedians in the "Original Kings of Catchphrase Comedy" video series. • Drunk Uncle, an extremely inebriated and bitter character who drunkenly rants and raves during
Weekend Update. • Janet Peckinpaugh, a middle-aged woman who hooks up with male celebrities, she hooked up with
Tom Brady (as played by Channing Tatum) and Adam Levine as himself. • Niff, a retail worker who, along with Dana (
Cecily Strong) always insults retail workers whenever they fear they're going to get fired. • Kirby, an astronaut obsessed with his "little kitty cat". • Riblet,
Michael Che's high school friend on Weekend Update.
Celebrity impressions •
Bill Belichick •
Ken Bone •
Susan Boyle •
Chris Christie •
Mindy Cohn •
David Crosby •
Ted Cruz •
John Daly •
Danny DeVito •
Josh Duggar •
Guy Fieri •
Jared Fogle •
Rob Ford •
Barney Frank •
James Gandolfini (as
Tony Soprano) •
Jeff Garlin •
Newt Gingrich •
Jonah Hill •
Mike Huckabee •
Kim Jong-un •
Rob Kardashian •
Brian Kilmeade •
Nathan Lane •
George Lucas •
George R. R. Martin •
Rosie O'Donnell •
Psy •
Seth Rogen •
Kevin Smith •
Snooki •
Steven Seagal •
Donald Sterling •
Glenn Thrush •
Andrea Bocelli ==Personal life==