Justin Timberlake has joined the cast of Columbia Pictures' comedy Bad Teacher starring along with Cameron Diaz, Jason Segel, and Lucy Punch, it was announced today by Doug Belgrad and Matt Tolmach, presidents of Columbia Pictures. Eric Stonestreet from Modern Family and Molly Shannon have also joined the cast of the comedy, which centers on an irreverent middle school teacher. Directed by Jake Kasdan and written by Lee Eisenberg & Gene Stupnitsky, the film is produced by Mosaic's Jimmy Miller and begins production later this month.

Commenting on the announcement, Belgrad said, "With Justin, Molly and Eric, joining Cameron, Jason, Lucy and the rest of this dream comedy cast, we couldn't be more excited about this movie. We love what we've seen of Justin's performance in David Fincher's The Social Network and he is a perfect match for this role."

Justin Timberlake will play a key role as a substitute teacher, the scion of a watch fortune.

The comedy is being overseen at Columbia by Belgrad and Jonathan Kadin. For film related endeavors, Timberlake is represented by Rick Yorn, Jennifer Davisson Killoran, WME and Ziffren Brittenham LLP.