One Fine Dayis a 1996 American romantic comedy film directed by Michael Hoffman , and starring Michelle Pfeiffer and George Clooney as two single working parents, with Alex D. Linz and Mae Whitman as their children. The title comes from the 1963 song " One Fine Day " by The Chiffons .

Michelle Pfeiffer served as an executive producer on this film,which was made in association with her company Via Rosa Productions.

The film was nominated for an Academy Award for Best Original Song ("For the First Time").

Melanie Parker ( Michelle Pfeiffer ) is an architect and divorced single mother to son Sammy ( Alex D. Linz ). Her day gets off to a bad start when she is late to drop Sammy off at school, due to the forgetfulness of fellow single parent Jack Taylor ( George Clooney ), aNew York Daily Newsreporter whose daughter Maggie ( Mae Whitman ) is thrust into his care that morning by his ex-wife.

The children arrive seconds too late to go on a school field trip. Their parents are forced to accept that, on top of hectically busy schedules, they must work together to supervise each other's children.

Melanie must make an architectural design presentation to an important client. Jack has to find a source for a scoop on the New York mayor's mob connections. Sammy causes havoc at Melanie's office with toy cars, causing her to trip and break her scale model display.

In frustration, Melanie takes Sammy to a child daycare centre (which is having a "Superhero Day"), where she comes across Jack trying to convince Maggie to stay and behave herself. They create impromptu costumes for the children, utilising Jack's imagination and Melanie's resourcefulness.

Having left for a meeting, Melanie panics when she receives a phone call from Sammy regarding other children and drugs. She phones Jack in desperation to ask him to pick up both kids. He agrees on the condition that she take them at 3:15 while he chases down a potential source.

While in Melanie's care, Maggie goes missing. Melanie breaks down in despair at the police station, files a missing child report and goes to a mayoral press conference to find Jack. He is notified by the police that Maggie has been found and makes it to the press conference just in time to confront the mayor with his scoop.

Although the two have been antagonistic, Melanie and Jack work together to get both Sammy and Maggie to a soccer game. Melanie insists that she will have time to do her presentation to the new clients, despite Jack protesting that it will make them late for the game. Melanie begins her pitch, but upon seeing Sammy in high spirits, she realises that she cares more about her son than her job. Bravely insisting that she must leave immediately to be with her son, she fully expects to be fired, yet the clients are impressed.

At the game, Melanie meets her ex-husband, who admits that he has lied to Sammy and that he is going on tour as a drummer with Bruce Springsteen . That evening, Jack wants a reason to visit Melanie's apartment, so he takes Maggie to buy goldfish to replace the ones that were eaten earlier in the day by a cat.

At Melanie's apartment, the children watch TV while Jack and Melanie share an awkward first kiss. Melanie goes to the bathroom to freshen up; when she returns, an exhausted Jack is asleep on the sofa. Melanie joins him and they fall asleep together.