There's a thin line between directing and acting, which explains why so many celebrated actors have taken a turn behind the camera (Robert Redford, Warren Beatty, George Clooney, Ben Affleck, Barbra Streisand, Kevin Costner and Sarah Polley are just a few of the more acclaimed examples). It would also explain why so many directors have chosen to step in front of the camera—whether for a quick cameo or a leading role.

Here, we're Evaluating the Acting Chops of 20 Directors Who Cast Themselves. It's gonna get nasty.

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Written by Jennifer M. Wood (@j_m_wood)