The PCs come across a town with a strange curse: Every morning, those who have grown up here wake up with the memories of someone else. They do not find this strange and have no idea it is happening. They calmly wake up and start these new lives as though they have always been that way.
The cause: A wizard who lived there was spurned by a maiden he was infatuated with. His attempt to manipulate her memories into believing they were already together and that she loved him went horribly awry.
It is rumoured that a sort of little people living deep in the green woods have magic acorns. If they throw and hit someone with by one of these acorns the victim will experience temporary madness for a small duration of time, making the babbling victim easy to capture of kill.