Mulligan began the 1970s with "The Pursuit of Happiness" (1971), based on the 1968 novel by Thomas Rogers, which had been a finalist for the National Book Award. The film starred Michael Sarrazin as William Popper, a college student (disillusioned with both right-wing and left-wing American politics) whose life is complicated when he accidentally runs over and kills an elderly woman and is quickly sentenced to one year in prison for vehicular manslaughter. He then contemplates breaking out of prison and fleeing the country with his girlfriend (played by Barbara Hershey), since neither feels their lives have made any significant difference in America.