When was the last time you truly used, focused on, for any significant length of time, your imagination; your active, conscious, willful, artistic creativity, to get back in touch with that ability to appreciate the wonder that you yourself can create and bring forth, all from within yourself? Were you ever able to do that? Did you ever do that? Can you still do it? Do you do it when you game, as player or GM? Will you do it? Could this be missing from a lot of the newer, younger RPG'ers of today?
The PCs find a strange helmet, when donned it will take control of that PC and speak and act trough him/her. It explains that it is benevolent and needs their help in a quest and that it will stop possessing the PC when the task is done. Great if a player is gone for a number of sessions.