Jack Campbell is a high-flying New York investment broker about to seal the multi-billion dollar deal of the century, when he helps to stop a drug-store robbery and suddenly his life is turned upside-down by the angelic Don Cheadle. He wakes the next morning in an alternative reality where he has married his old flame Kate (Tea Leoni), has two kids and a dog, and lives outside the big city selling car tyres for a living...

Jack's new life starts to grow on him, until he finally realises that his old life (although luxurious) was empty without the love of his wife and kids.
  While outside with the kids in the garage, little Annie starts ringing the bell on her bike and Jack panics. (The bell is the signal that it is all about to end).  Jack goes to the corner store to get some eggnog and Don Cheadle is serving behind the counter. Jack is scared and yells that he wants to remain where he is, while Don tells him that it was only ever a 'glimpse' at a different life.
  Next day Jack wakes up in his luxury apartment and previous life, and knows what he has to do. He turns away the date that shows up on Christmas Eve, and forgets about work and the big deal as he tries to find and win-back Kate.

Kate is busy moving offices and leaving the country, and she can't spare Jack much time. Jack picks up his old box of stuff, but wants to fight for the alternative life they can have.
  He follows her to the airport, makes a big scene at the security gate, and she decides to give him a chance and get some coffee together.
  The movie ends with them talking together at a table, having coffee, talking late into the night and making plans for the future.