2-"Eternal Sunshine of the Spotless MInd": when we first see Jim Carrey, he meets Kate Winslet at a train. They fall in love, but then they break up. She goes to Lacunas to wipe out all memories of him, and then he retaliates by doing the same. But when they show his memories, the train is nowhere to be seen and they meet at a beach. Which means that they met, fell in love, and wiped their memories of each other, only to meet AGAIN, fall in love AGAIN, and wiped out the memories of each other AGAIN.
See? Too complicated for me to follow.