Travis Bickle, a 26-year-old honorably discharged U.S. Marine, is a lonely, depressed young man living on his own in New York City. He becomes a taxi driver to cope with his chronic insomnia, driving passengers every night around the city’s boroughs. He also spends time in seedy porn theaters and keeps a diary. Travis becomes infatuated with Betsy, a campaign volunteer for Senator and presidential candidate Charles Palantine.