Commitment shy Henry Roth (Adam Sandler) is a care-free bachelor working at a zoo in Hawaii, happily moving on from one holiday romance to the next - until he meets Lucy (Drew Barrymore) and instantly knows that he may have found 'the one'. Problem is - the next day Lucy doesn't even remember him. After an accident she suffers from acute short-term memory loss - so to win her heart, he needs to win her over again ... and again ... and again...!

Lucy overhears Henry talking with her dad, Doug and the doctor about postponing his plans to film wildlife in the Arctic. Not wanting to take away his dreams - she tears out select pages from her diary to erase him from her life. Henry sets sail, while Lucy goes to help at a hospital for people with a condition like her own.
  Suddenly Henry remembers something Lucy's father told him - that she only sings after they share a date. He rushes back to shore and races to the hospital to meet her. He asks if she remembers him - but she doesn't.
  She asks him to follow her to an art cupboard - which is filled with paintings of Henry. She says that she dreams about him every night. That's clinched it, and they're back together again.

Later, Lucy wakes as normal and watches the video by her bedside to get her accustomed to her new life - but when looking out the window she realises that she's on a boat in the Arctic Ocean! She gets to the top deck to find that she's on Henry's expedition - with her father, Henry ... and their young daughter.