Hangemuhl was part of the town's conspiracy of using a Soul eater to heal people. Fox Mulder came to the town to question them, but Hangemuhl tried hard to dismiss the story and his questions. Later, Mulder came to his house and killed the creature.
John Doggett later that year came to question Hangemuhl and his wife about Mulder, but they still did not say a lot, other than confirming he had called them that May. In fact, the creature had been found to have been brought back alive, and they were keeping it secret.
As Marie had a kidney disease, she was in need of the creature, but hesitant to use it. Hangemuhl convinced her, and she was cured, waking up in the woman's house. Doggett had gone there and found her in the cave, rescuing her and bringing her home. (TXF: "The Gift")