Failed author Ben Tyler (Joshua Jackson) is diagnosed with stage 4 cancer. His chances of survival are 10%. His fiancee Samantha entreats him to begin treatment immediately, but instead he sets out on a motorcycle trip from Toronto to the west coast.
Samatha flies out to join him in Banff, where he admits he doesn't love her as she should be loved and they break off their engagement. Ben continues west until he reaches the Pacific Ocean (Tofino, British Columbia). He goes surfing and sees a whale, which he takes as a sign to return home to Toronto. He says farewell to Samantha and is reunited with his family.
The narrator concludes with the words "If you had one week to live, what would you do? What book would you write?". The narrator is reading from a book titled One Week by Ben Tyler. A bookstore filled with copies of this book is shown, a photograph of Ben's motorcycle on the cover, indicating that Ben wrote this book about his trip.
It is not stated, but the implication is that Ben eventually died of cancer.