Architect Sam Baldwin (TOM HANKS) and his young son Jonah (ROSS MALINGER) have recently lost a beloved wife and mother. Even though Sam has Jonah to get him through it, he still feels pangs of loneliness and Jonah notices this enough to call a nationwide radio talk show to explain to the host that he thinks his father needs a new wife.
All the way in Baltimore, Annie Reed (MEG RYAN), a writer for the Baltimore Sun, hears Sam's talk on the radio about how much he loved his wife and is deeply affected by it. She's curious about who Sam is and if perhaps he is actually the right one for her and not Walter (BILL PULLMAN), whom she is engaged to and who is allergic to nearly everything.
With the help of their various respective friends, and as Sam dates Victoria (BARBARA GARRICK), they try to figure out their futures, all while Jonah tries to get them together.