Simon and Robyn are a young married couple whose life is going just as planned until a chance encounter with an acquaintance from Simon's high school sends their world into a harrowing tailspin. At first, Simon doesn't recognize Gordo, but after a troubling series of uninvited encounters and mysterious gifts, a horrifying secret emerges. As Robyn learns what really happened between Simon and Gordo, she begins to question how well she knows her spouse.