Workaholic Tess Harper, who always feels the need to come to everyone's rescue at the expense of her own relaxation, is a doctor at Bayside General Hospital in Boston. She welcomes playing that white knight role with her boyfriend of two years, stockbroker Dex Richmond, and her best friend since childhood, Amber Tilton, whose wedding to her boyfriend Jack will be taking place this weekend at a resort outside of Chicago, and which Tess and Dex will be attending, Tess as maid of honor.
Tess sees the trip to Chicago as an opportunity to grease the wheels in her bid to earn a fellowship at Northwestern University - a member of the selection committee who will be attending the wedding - but also to convince Dex, a confirmed Bostonian, not only to fall in love with Chicago, but ask her to marry him in the process in the hopes of having their future in the Windy City, closer to where she grew up. To further his own career, Dex, at the last minute, bails on attending the wedding.
At the resort, Tess immediately starts to butt heads with the best man, Michael, a divorce lawyer. Tess, who believes in love and marriage, cannot deny any request in seemingly being the chief firefighter in putting out fires not only by Amber but by anyone else in wanting to make the wedding perfect for Amber. Michael, on the other hand, is seemingly hiding something in his past which makes him cynical about weddings and marriage more than just in a professional sense, while he just wants to take advantage of all that the resort has to offer to relax.
In their roles in standing up for the bride and groom, Tess and Michael may need to find that balance of ensuring that the wedding happens without a hitch, while it, which is supposed to be a fun and happy occasion, is also fun and happy for them as participants. In the process, they may both discover what they want for their future personal lives, and that not everything that happens at the wedding happens by accident.