After the death of his wife, Sam Baldwin (Tom Hanks) moves to Seattle with his son, Jonah (Ross Malinger). When Jonah calls in to a talk-radio program to find a new wife for his father, Sam grudgingly gets on the line to discuss his feelings. Annie Reed (Meg Ryan), a reporter in Baltimore, hears Sam speak and falls for him, even though she is engaged. Unsure where it will lead, she writes Sam a letter asking him to meet her at the Empire State Building on Valentine's Day.

A dark-haired woman (Laura Elena Harring) is left amnesiac after a car crash. She wanders the streets of Los Angeles in a daze before taking refuge in an apartment. There she is discovered by Betty (Naomi Watts), a wholesome Midwestern blonde who has come to the City of Angels seeking fame as an actress. Together, the two attempt to solve the mystery of Rita's true identity. The story is set in a dream-like Los Angeles, spoilt neither by traffic jams nor smog.