In the last couple of years, a head-scratching headline has popped up from time to time: Can an animal be a person? That question is the subject of a new documentary by Oscar-nominated filmmakers Chris Hegedus and D.A. Pennebaker. “Unlocking the Cage” follows attorney Steven Wise as he tries to get the courts to acknowledge that an ape is a person - not in the biological sense, but in the legal sense - giving them certain rights, the way corporations have rights.