[1] Harrison's mother, Pamela Greenbaum, stated in 2010 that Harrison's paternal grandmother "told the serious stories about the Holocaust camps" while his paternal grandfather Henry Greenbaum, also a Holocaust survivor, “told the humorous stories."

", premiered at the Upright Citizens Brigade Theatre in New York City, marking the venue's first magic show.

The show then had an Off-Broadway run and embarked on an international tour, with performances at the Kennedy Center in Washington, D.C., the Magic Castle in Hollywood, California, and the Comedy Cellar in New York City, where it was also the first magic show to be performed at the venue.

[17] Greenbaum was an official co-host of the 2010 Times Square New Year's Eve World Wide Webcast[18][19][20][21][22] and was the host of the New York Innovative Theatre Awards, held at Cooper Union's Great Hall in 2011[23][24][25] and at Kaye Playhouse in 2012.

He is also the winner of the 2011 Magners Comic Stand-Off and a 2011 Shorty Award for excellence in short-form social media (i.e.

[32] Greenbaum was named one of 2010's "Comics to Watch" by Comedy Central[33][34] and one of the "Best of the Breakout Artists" by Carolines on Broadway and Punchline Magazine.