A doctor runs in a grueling 24-hour, 100-mile ultramarathon over rugged mountain terrain as he avoids the aftermath of a recent incident in his medical practice. Over the course of the marathon, as physical and mental exertion turns to exhaustion and hallucinations, race-related dramas intertwine with the details of his current crisis. He's tormented by his decision to assist in the death of a terminally-ill teenager under his care, against both the parents' wishes and the legal parameters of assisted suicide.