Dan Stevens' departure from "Downton Abbey" at the end of Season 3 left fans distraught -- how would the show survive without the beloved Matthew Crawley? (In truth, Season 4 was a bit dull.) But Stevens wanted to pursue other acting projects, one of which is Adam Wingard's "The Guest."

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Stevens plays a soldier who introduces himself to the Peterson family, claiming to be a friend of their son who died in action in Afghanistan. But after the young man is welcomed into their home, a series of accidental deaths seem to be connected to his presence. 

From the looks of this trailer, Stevens has left nice guy Matthew behind for good, and has embraced a bit of the bad boy inside. "The Guest" will be released by Picturehouse in September. Check out the teaser trailer below: