In this romantic drama, a lonely doctor and a frustrated architect discover a mysterious mailbox at a lake house where they have both lived at different times. The doctor, having just moved out, leaves a note for the next tenant only to receive a reply from the architect who, to her surprise, claims to be living in the year 2004, two years before her time in 2006. As they continue to exchange letters through this mailbox, which somehow bridges their two time periods, they begin to uncover the deep connections and shared experiences that link them together despite the impossible temporal gulf that separates them.

As their correspondence evolves, the two protagonists find themselves falling in love, despite the challenges posed by their unique situation. They share insights about their lives, hopes, and the paths that have led them to the lake house, wrestling with the constraints of time and the longing to somehow make their burgeoning relationship work in the face of the seemingly insurmountable barriers that time has placed between them. The lake house itself, with its beautiful but haunting presence, serves as a poignant backdrop to their growing connection, symbolizing both the distance and intimacy that define their relationship.