The cast of Relativity Media's Untitled Heist Comedy (formerly known as Loomis Fargo) has added Ken Marino, Kate McKinnon, Mary Elizabeth Ellis, Devin Ratray, Ross Kimball and Leslie Jones, who join Owen Wilson, Zach Galifianakis, Kristen Wiig and last week's addition Jason Sudeikis.

The plot is based on the true story of a group of bungling Southerners who managed to pull off a $20 million heist. Zach Galifianakis plays David an armored truck driver who is coerced by his workplace crush Kelly (Kristen Wiig) and her accomplice Steve (Owen Wilson) to take part in a heist she is planning. After they pull off the job, David goes on a vengeful journey after he is abandoned in Mexico while Kelly and Steve are off living the high life.

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Ken Marino is playing the affluent Doug Jeffcoat, who has issues with Steve and his friends moving into his wealthy neighborhood. Kate McKinnon will portray David's "ball-busting fiancee," and Mary Elizabeth Ellis is playing the gold-digger who is married to Steve. Devin Ratray and Ross Kimball play Steve's loyal thugs Runny and Eric, while Leslie Jones rounds out the cast as a detective who is tracking these criminals down.

Jared Hess is directing from a script originally written by Emily Spivey (Up All Night), which was rewritten by Chris Bowman and Hubbel Palmer. Lorne Michaels and Tony Goldwyn are producing, with Danny McBride, Jody Hill, Kevin J. Messick, Erin David, Ryan Kavanaugh and Tucker Tooley executive producing. It isn't known when production may begin, but Relativity has already issued an August 14, 2015 release date.