The Nine Lives of Fritz the Cat(1974)

Overview:

Fritz, now married and a father, is desperate to escape the domestic hell he now finds himself in. Lighting up a joint, he begins to dream about his eight other lives, hoping to find one to provide a pleasant distraction. The drug-induced journeys he takes include spells as an astronaut, Hitler's psychiatrist, a courier travelling in hostile territory during a race war, and as a pupil of an Indian guru in the sewers of New York.