Mary Ann “Pookie” Adams is a quirky teenage oddball who meets quiet, reserved Jerry Payne while waiting for a bus heading to their colleges; both are freshmen and their colleges are near each other. Jerry immediately sees that Pookie is different, even strange: she lies to a nun on the bus so the nun will switch seats with her.
As Jerry is beginning to settle into college life with his roommate, Charlie Schumacher, the aggressive Pookie arrives unannounced one Saturday morning. Pookie and Jerry spend much time together over the weekend, and soon begin to see each other regularly.
Jerry falls in love with Pookie, but their different personalities start to pull them apart. After they have sex, Pookie tells Jerry she might be pregnant. When the pregnancy scare is over, Jerry wants to spend spring break alone to catch up on his studies. Pookie pleads to stay with him, and he relents.
A week alone with the needy, somewhat unstable Pookie makes Jerry realize that they need time apart. Later he discovers that she has dropped out of school, and he finds her in the same boardinghouse where she had been staying the first time she visited him. He puts her on a bus for home and the young lovers part ways.