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Smith will play Deadshot, best known as a Batman villain, while Hardy plays the group's leader, Rick Flagg.

Leto will take on the Joker, while Robbie will play Harley Quinn, his on-and-off girlfriend. Courtney will be Boomerang, while Delevingne, the model-turned-actress who is also in Warners' Pan tentpole, will play Enchantress, a sorceress.

David Ayer is writing the script as well as directing.

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Charles Roven and Richard Suckle are producing. Exec producing are Zack Snyder and Deborah Snyder, who are already shepherding many of the DC movies, as well as Colin Wilson and DC's COO Geoff Johns.

Jesse Eisenberg, who was rumored to be involved with the movie, is not part of the official team, nor the official cast, according to sources. But that does not rule out a cameo appearance for him or other actors playing villains or heroes in the Warners' other DC-based movies.

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"The Warner Bros. roots are deep on this one," said Greg Silverman, president, creative development and worldwide production, in the announcement.

"David Ayer returns to the studio where he wrote Training Day and brings his incredible ability to craft multidimensional villains to this iconic DC property with a cast of longtime Warner collaborators Will Smith and Tom Hardy, and other new and returning favorites: Margot, Jared, Jai and Cara," Silverman continued. "We look forward to seeing this terrific ensemble, under Ayer's amazing guidance, give new meaning to what it means to be a villain and what it means to be a hero."

The movie has a release date of Aug. 5, 2016.