After being a long time in a relationship Anna Brady (Amy Adams) is going to a romantic dinner with her boyfriend Jeremy (Adam Scott). There she was expecting to see the ring and a marriage proposal with that. But, all she gets is a pair of nice earrings. After that she has decided that she doesn't want to wait for her stuck up boyfriend to propose to her. Instead, she is going to do it. And as one of the old traditions says, she can propose to him on Leap Day, which is on February 29th, and if she does, he doesn't have the way to say no. So, after one night of thinking, she decides to go to Dublin, where he is on a conference, and propose to him. She gives her pair of earrings and replaces them for a ring. She plans it all and gets on the plane. But, due to bad weather, her plane is forced to take down in Wales. Now, she must find the way to get to Dublin in time. In a bar one guy offers to take her to Dublin with a car and she accepts. From that point on, it's all but what she had planned.. and that includes the guy she wants to propose to as well. After some time spent with this stranger, she starts falling for him and in the end finds herself in the doubt who to marry.