Two people named Thomas "Tom" Bailey Jr. (Patrick Dempsey) and Hannah (Michelle Monaghan) who met by accident during one Halloween Night in college. They became platonic best friends throughout their college lives and experience life growing old together. Tom, being the man-of-the-world, has a set of rules in dating women and he shares his experiences with Hannah. While he is busy with his dating escapades, Hannah sits quietly on one side taking all this in a stride. When Hannah mentions to Tom that she will be traveling to Scotland, Tom suddenly sees that Hannah is just not the girl to hang out with. During her stay abroad, he misses her terribly and suddenly thought she is the ONE meant for him all along. When Hannah arrives back home, Tom plans to take their relationship on a deeper level. Unfortunately, Hannah brought someone from Scotland and divulged mind-blowing news -- she's engaged to be married to that Scottish guy, asks Toms to be her Maid-of-Honor and help plan the wedding in less than 6 weeks! The story thickens as Tom plots his strategies to "STEAL THE BRIDE". The story winds through the events that will everyone curious what will happen next.