Phil Connors is a TV weatherman who thinks that his current job at a local Pittsburgh station is a waste of his talent. The guy's basically an egomaniac, so he definitely isn't impressed when his bosses send him off to the small town of Punxsutawney, Pennsylvania to cover the annual Groundhog Day festivities.
Phil gets through the day by doing the bare minimum to perform his job. But when he tries to head home, a blizzard keeps him in Punxsutawney. Phil spends the night and wakes up the next day to find that he has to live Groundhog Day all over again. And again. And again.
Phil's early reaction to reliving the same day is to use his knowledge of Groundhog Day for selfish purposes. For example, he steals some bank money and uses his intel to trick a pretty woman into sleeping with him. Then he sets his sights on his producer, Rita. But he eventually realizes that no matter how many times he attempts to seduce her, she'll always see through his selfish games.
After a while, Phil realizes that he'll never escape Groundhog Day. That's when he decides to kill himself. But no matter how many times he tries, he keeps waking up back in his bed at 6:00AM on February 2nd.
Finally, he gives up on himself entirely and devotes himself to helping others. He even tries to save the life of an old homeless man, but eventually finds that no matter what he does, this man is destined to die on Groundhog Day. Yep, Phil has learned another valuable lesson: there are some things he just can't change.
Now that Phil has learned to forget about his ego and to accept the things he can't change, he starts to become a better person. This new approach to life pays off, as he wins the heart of Rita and finally escapes his imprisonment in Groundhog Day.