One of American independent Robert Kramer’s strongest “underground” features (1969), arguably his best, made in and around New York before he resettled in Paris. This potent and grim SF thriller about urban guerrillas of the radical left, shot in the manner of a rough documentary in black and white, has an epic sweep to it. (Like many politically informed art movies of the period, starting with Alphaville and including even THX 1138, it was set in the future mainly as a ruse for critiquing the present.) Now as then, the power of this creepy movie rests largely in its dead-on critique of the paranoia and internecine battles that characterized revolutionary politics during the 60s; the mood is terrorized and often brutal, but the behavioral observations and some of the tenderness periodically call to mind early Cassavetes. A searing, unnerving history lesson, it’s an American counterpart to some of Jacques Rivette’s conspiracy pictures, a desperate message found in a bottle.