Marie Hangemuhl was a resident of a small town in Pennsylvania and wife of Paul Hangemuhl.
Hangemuhl was part of the conspiracy to use a Soul eater to cure diseases among them. Fox Mulder had come to ask questions of her and Paul when she had reported that her sister was going to disappear. However, under Paul's watch, she hesitated to say much to him. She later screamed when Mulder came again later and killed the creature.
John Doggett later that year came to question Hangemuhl and her husband about Mulder, but she 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 Hangemuhl had a kidney disease, she was in need of the creature, but hesitant to it. Paul 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")