When a nun comes into the clinic with swollen arms, rash and bleeding in her palms, Dr. House’s diagnosis is a bad allergy, not stigmata. However, when he gives her a shot of medication, she has a heart attack, and whether he gave her the correct amount of medicine comes into question. As the the nun’s case unfolds, the team has to deal with questions regarding their own calling, faith and whether or not they can trust the direction in which their mentor is leading them.