Sherwin continued to perform with The Late Night Players after graduating from Brandeis until the group's dissolution in 2007. The group was the subject of a documentary directed by Joshua Goren which screened at the November 2006 New York International Independent Film and Video Festival. Sherwin began to perform solo as MC Mr. Napkins in
Boston from 2007 until giving up the name completely in 2013 in a video posted to his YouTube channel. As a solo comedian, Sherwin has performed multiple times at the
Knitting Factory. He has appeared in multiple shows at
UCB. Sherwin appeared on the debut episode of
Cameron Esposito's
Aspecialthing-produced stand-up comedy podcast
Put Your Hands Together. Sherwin was one of the original performers involved with the
Epic Rap Battles of History YouTube series. As of May 2024, he has appeared in eleven episodes, having portrayed
Albert Einstein,
Emmett Brown,
Sherlock Holmes,
Ebenezer Scrooge,
Stephen King,
Egon Spengler,
Voltaire,
Walt Disney,
Alexander the Great,
Wayne Gretzky, and
John Wick. Along with co-creators
Peter Shukoff and
Lloyd Ahlquist, Sherwin has written for episodes in every season of the series and has acted in every season except season 6. In 2014, the series won a
Streamy Award for Best Writing. In 2015, the series was nominated for the same award. In 2016, the series was nominated for Streamy Awards for Best Collaboration and Best Writing. From 2015 to 2017, Sherwin worked as a songwriter for the
CW series
Crazy Ex-Girlfriend. He co-wrote the songs "JAP Battle", "JAP Battle (Reprise)", "I Give Good Parent", and "So Maternal". The first season of the series was nominated for multiple awards and holds a 96% positive rating on
Rotten Tomatoes. Sherwin auditioned for
season 11 of ''
America's Got Talent'' in 2016. His performance in the Judge Cuts round was televised but he did not proceed to the Quarterfinals round. Sherwin writes, produces, and hosts a series of live
crossword puzzle comedy shows entitled
The Crossword Show, in which three panelists race to solve a crossword puzzle on stage. The shows include comedy raps, videos, and humorous facts prepared for each clue. The format is similar to
NPR's ''
Wait Wait... Don't Tell Me!''. Notable guest solvers have included
Mayim Bialik,
Pete Holmes,
Rachel Bloom,
Lisa Loeb,
Josh Gondelman, and
Aparna Nancherla. ==Personal life==