The Lake House is a mysterious and somewhat paranormal romance movie. The movie stars Sandra Bullock as Kate and Keanu Reeves as Alex. The house on the lake is rented by both characters at different times in their lives. While Alex is renting the house, he finds a letter in the mailbox written by Kate requesting that her mail be forwarded to her new address. She also mentions a set of dog prints which are embedded into the walk leading up to the house. The first strange occurrence is when Alex, who is renting the house two years prior to when Kate did, acquires a dog who leaves his prints on the walk.
Alex decides to respond to Kate's letter by writing her back and leaving it in the mailbox for the postman to pick up. He is surprised when as soon as he closes the mailbox door the red flag goes up indicating the box has received mail. He opens the door and finds a new letter from Kate. The majority of the interactions between these two characters takes place via the magic mailbox which seems to defy the laws of time. After a while several months have passed and the two characters have found themselves sharing personal information with each other, which begins to draw them close.
After some time, the characters agree to arrange some type of meeting, only to have the events surrounding their meeting take a disastrous turn. Because Kate is two years behind Alex in time, she witnesses an accident which leaves a man dead. This happens at the arranged time the two were supposed to meet. In an effort to prevent Alex from coming and being killed in the accident, Kate rushes back to the lake house to leave one final note asking Alex not to go to the arranged meeting place.