For one night only, a raggedy group of circus performers are upended by a train crash and stranded in Walpole, Maine. In “Circus 196977,” a mysterious documentarian encounters the group in a large barn and tracks their medley of song and dance. The film features avant-garde dance sequences paired with varied pieces of pop music in-between spoken interludes from each of the performers. Filmed in the dead of the night, the film bridges elements of an eerie found-footage style horror film with a un...