Overly regimented and risk-averse San Francisco-based Madeline Zekko is planning her and her fiancé Jason Reid's honeymoon to Niagara Falls to take place in five weeks time, Madeline not leaving a second free in the itinerary in wanting to recreate her grandparents' love story there. Instead, Jason, who wants some spontaneity in life and accusing Madeline of not having a spontaneous bone in her body, breaks up with her. Madeline's divorced sister Harley is ultimately able to convince Madeline to take that pre-paid, non-refundable honeymoon trip with her to show Jason that she can indeed be spontaneous. When Madeline and Harley arrive at the tour company's office on their second day in Niagara Falls, Madeline is dismayed to see that their tour guide for the week Mike Hollis, the man with who she had a less than pleasant encounter the day before. With Mike's boss and best friend Emily Henley unable to take over Madeline's tours in working on her own tours for her brother Keegan's best friend Phil and his fiancée Beth who will be getting married at the end of the week, Emily is able to convince both Madeline and Mike to give going on the tours together a try. Mike is further able to convince Madeline to change the itinerary somewhat to incorporate adventure activities, Mike's preferred ones as opposed to the plethora of romance tours that are their bread and butter, again to demonstrate to Jason that she is not totally stuck in her box. In the process with Mike opening up about his two year heartache in who he thought was the one leaving him, Madeline and Mike see a different side of the other as they start to fall for each other, Phil and Beth who end up being a sounding board in being able to provide some insight into why their relationship works. A kink in Madeline opening herself up fully to Mike is Jason, for who she went through the motions of this faux honeymoon.
