A rich American industrialist gives Tom Ripley the task of bringing his son Philippe home. Tom, also a former friend of Philippe, finds him in Italy enjoying himself with his mistress Marge Duval and with no intention of returning to the U.S.A. Tom, thinking his mission to be over, takes advantage by taking a holiday with Philippe. However, things soon go badly wrong. Humiliated by Philippe and driven up the wall by his friend's father, Tom commits the perfect crime by killing Philippe and taking over his bank account. Nevertheless he eventually loses control of the situation after committing a second crime.