Come play with me
~ Peter

Peter Sweeney is the main supernatural antagonist in the Supernatural season 1 episode Dead in the Water.

Peter was a schoolkid in the town of Lake Manitoc and he was the smallest kid in the school so the two bullies Jake and Bill often laughed at him. Jake one day thought it was funny to hold Peter's head inside the water and it was under for too long so Peter drowned.

Fifty years later Peter retuned as a ghost and began drowning anyone who floundered or swam in the lake. Peter was a merciless spirit and killed seven people altogether, the latest victim was Bill's older daughter.

Peter's mother had been left alone since Peter's death and when Sam and Dean went to investigate the drowning they found Jake and Dean met Jake's daughter Andrea and her son Lucas. Jake, who ironically was now police chief, was the more optimistic of the two bullies and charismatic, his friend Bill was a recluse and never spoke to anyone.

Peter Sweeney drowned Bill's other child, his son, and it was an odd death as he drowned on land in his kitchen sink. Then Peter went for Jake's family, Andrea and Lucas, right after Bill committed suicide by letting Peter's ghost take him because he knew it was a ghost. Andrea was almost drowned in her bath and Sam dragged her out before Peter could kill her. Peter Sweeney later targeted Lucas as he was playing near the lake. It was revealed Lucas' father had been drowned by Peter and this traumatized Lucas into silence. Lucas was suddenly thrown into the lake by Peter's ghost who showed himself to Jake, alarming him. Jake was distraught about Lucas' supposed death and begged Peter to take him instead, and Peter dragged Jake to the Underworld.