Even 20 years of service was not enough for them - still they taunt me. Will I ever be free?
the Apple Tree of Selilion holds the secret of life and death
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.