John Cariani is a Tony Award nominated actor and an accomplished playwright. As an actor, he is best known for his roles on NBC's Law & Order (as Forensics Tech Beck), on CBS' Numbers (as Professor Otto Bahnoff), and on IFC's The Onion News Network (as reporter Michael Falk). Notable film work includes Showtime (with Robert De Niro), Scotland, PA (with Christopher Walken), and Elephant Sighs (with Ed Asner).

On stage, he is best known for his work on Broadway. He received a Tony Award nomination and an Outer Critics Circle Award for his portrayal of Motel the Tailor in the 2004 revival of Fiddler on the Roof. He originated the role of Nigel Bottom in the Broadway hit, Something Rotten!, and received an Outer Critics Circle Award and a Grammy Award nomination for his performance. He also originated the role of Itzik in the The Band's Visit, winner of the 2018 Tony Award for Best Musical, and he recently appeared as Stuart Gelman in the acclaimed revival of Caroline, or Change, receiving a Grammy Award nomination for his performance.

As a playwright, John is best known for his first play, Almost, Maine, which is one of the most popular plays in the United States with over 5000 productions to date. Almost, Maine is the most frequently produced high school play of the past decade, and has received over twenty international productions to date, having been translated into over a dozen languages. John's play, LOVE/SICK, has received over 500 productions worldwide.

John is also a novelist. Almost, Maine-a novel was recently published by Fiewel and Fiends, an imprint of MacMillan.