After a brief encounter with David Hammond, an old college friend, successful lawyer Ellie Warren tries to mend her marriage with her husband Marcus. But she finds herself caught in a terrifying game of cat and mouse when the encounter escalates into an obsession that jeopardizes everyone she loves.

In their finely appointed Connecticut home, Agnes and Tobias have grown used to the imperfection and fragility of their marriage. Quietly nursing their grief over the death of their son, they get by well enough together. Agnes' boozy sister wanders in and out, and they allow anxiety-stricken friends to move into an upstairs room. But, when their daughter, Julia, shows up announcing her fourth divorce, long-repressed emotions come to the surface.

A wife spends their anniversary waiting for her husband to finish a call, as their troubled marriage faces challenges.