Christopher Caldwell and Zeek Earl wrote and directed this intriguing but emotionally estranged bit of lo-fi sci-fi, an expansion of their 2014 short film of the same name. Sophie Thatcher stars as Cee, a resourceful teenager living outside of civilization with her father Damon (Jay Duplass), an outer space prospector in a hazily defined, largely analog alternate universe. As the first act slowly unfolds, it seems like we might be watching Leave No Trace in space, but everything changes when Cee and Damon discover an enormous deposit of valuable gems on the surface of a toxic planet. Suddenly, Cee is forced to team up with interplanetary bandit Ezra (Pedro Pascal) to avoid a gun-toting team of mercenary miners and get off the planet alive. A high-concept film that doesn’t explain itself to death is refreshing, but the margins of Prospect are far more interesting than the central story and characters. D.B.