The narrator bids us listen and declares that “Billy Pilgrim has come unstuck in time.” Billy travels randomly through the moments of his life without control over his chronological destination. Born in 1922 in Ilium, New York, Billy grows up a funny-looking weakling. He graduates high school and trains to be an optometrist before being drafted. After his military service in Germany, he suffers from a nervous collapse and is treated with shock therapy. He recovers, marries, has two children, and becomes a wealthy optometrist.
In 1968, Billy survives a plane crash in Vermont; as he is recuperating, his wife dies in an accident. After returning home, Billy goes on a radio show in New York City to talk about his abduction by aliens in 1967. His twenty-one-year-old daughter, Barbara, discovers his proselytizing and brings him home, concerned for his sanity. The following month, Billy writes a letter to his local paper about the aliens.
The day the letter is published, Billy is hard at work on his second letter to the Ilium newspaper about lessons he learned when he was taken to the planet Tralfamadore. He is glowing with the expectation that his letter will console many people by explaining the true nature of time. Barbara is distraught by his behavior. She arrives at his house with newspaper in hand, unable to get Billy to talk sense.
Billy describes his entry into the army, his training as a chaplain’s assistant in South Carolina, and his dazed trek behind enemy lines after the disastrous Battle of the Bulge in World War II. After the battle, Billy falls in with three other American soldiers, two of whom are scouts and capable soldiers. The one who is not, the antitank gunner Roland Weary, is a cruel, insecure man who saves Billy’s life repeatedly in acts that he thinks will make him a hero.
Billy first time-shifts as he leans against a tree in a Luxembourg forest. He has fallen behind the others and has little will to continue. He swings through the extremes of his life: the violet light of death, the red light of pre-birth. He is then a small boy being thrown into the deep end of the YMCA swimming pool by his father, a proponent of the “sink-or-swim” method.
Billy time-travels to 1965. He is now forty-one years old and visiting his mother in a nursing home. He blinks and finds himself at a Little League banquet for his son, Robert, in 1958. He blinks again and opens his eyes at a party in 1961, cheating on his wife. Messily drunk, he passes out and wakes up again behind enemy lines. Roland Weary is shaking him awake.