It's 1967. It's Canada's hundredth anniversary. It's Expo 67. Everything feels vibrant and exciting. Not for seventeen year old Rose Johnson though. Instead of going to the Expo 67 like her mother had promised her, she's stuck spending her summer at her family's old estate on the shorelines of the St Lawrence River in the small village of Bic in Quebec. Her mother is dead now and to her father, she's still a child living in a made-up world. They both feel trapped in a house filled with remnants of happier days. It looks like it will be a tedious summer until one evening after the sun has set, Rose takes a long hike on the shores and she can't help the prickling feeling nagging behind her head that there's someone watching... something. Her mother used to tell her so many ghost stories. In that moment, she finds herself believing her. When the dead body of a local boy turns up on the shores the next morning, there is no doubt in Rose's mind-something unnatural did this. The cops say it's a suicide. Rose doesn't believe it. Drafting the help of Liliane and Elliot Tremblay, two siblings from the French side of the estate who can speak English, Rose is convinced that she can crack the case.