Holly Blossums, a little angel in Heaven: happy, content, and she’s not going anywhere, no way, no matter what Saint Peter tells her: Earth is one nasty place to live, and she’s not going back. Nobody cared or loved her back there.

Not true, Saint Peter tells her, as he pulls down a movie screen out of the air and invites her to sit down with him to watch the show. The film begins with 10-year old Holly giving her only valuable possession, a gold locket, to her best friend, 12-year old Roy. She tells him to give it to someone special someday. The next scene shows Roy putting wild flowers on her grave.

Saint Peter makes a deal with God at the last minute: since Holly's previous family was dysfunctional and unloving, she is allowed the two weeks before Christmas on Earth to pick her next set of parents. Saint Peter sends the Heavenly Dog with Holly to watch over her and tell her when it's time to go back to Heaven.

Holly lands in the middle of a busy street of a big city where she is almost killed by oncoming traffic. She runs to the sidewalk only to see her reflection; she's several feet taller, and is about 28 years old--a child in an adult body.

She quickly begins her mission to find her new Mom and Dad. Her search leads to places where good families are found. She finds Mom and Dad except they aren't married. Even worse, Dad is about to marry, what his 78-year old, ex-cop dad, Roy, thinks is the wrong woman.

After a mishap with the law, Holly and Roy discover their common past in the interrogation room. At first Roy doesn’t believe her, but she eventually convinces him.

What follows are the hilarious adventures where everything goes wrong as Holly and Roy try to break up Dad's engagement and have his attention directed to Mom.

It’s almost Christmas and the wedding to the wrong woman is the following day. On Christmas Eve, The Heavenly Dog appears, telling Holly it’s time to return to Heaven. She leaves, thinking her mission has failed.

But the wedding to the wrong woman gets cancelled, and Mom and Dad find each other and marry. One year later, they are the proud new parents of a bouncing baby girl; they decide to name her Holly in honour of the woman who disappeared one day and brought them together. Just before Roy dies of old age, his last wish is to pass on the gold locket to his newborn grandchild, Holly.

In Heaven, 78-year old Roy looks down on the Earth with Saint Peter and Peter announces, “Roy, it’s your turn now. And by the way, you and Holly will be next door neighbours and in the future, will be sharing the same sandbox.”