On a Valentine Day, Joel Barish (Jim Carrey) feels the impulse of going to Montauk instead of working. After spending the cold day on the beach, he meets Clementine Kruczynski (Kate Winslet) on the train station and they have a crush on each other. Joel and Clementine do not know that they were mates in the past. Joel has just erased Clementine from his memories when he found that Clementine did exactly the same, when their relationship ended. However, along his erasing process, Joel becomes astonished when he finds that he still loves Clementine and he does not want to lose her, fighting for keeping the memories of their moments together instead.