On the morning of July 20, 1981, David Allen Kirwan, a 24-year-old man from La Cañada Flintridge, and his friend Ronald Ratliff and Ratliff's dog Moosie, were driving through the Fountain Paint Pot thermal area in Yellowstone, Wyoming. They had no idea that they were about to experience the most terrifying event of their lives.

While exploring a thermal spring region, Moosie escaped from the truck and ran towards a nearby spring called the Celestine Pool, which had water temperatures above 200°F. The dog began yelping after jumping into the pool.

Kirwan, overcome with concern for the pet, disregarded the warnings of his friend Ratliff and the other onlookers and plunged headfirst into the searing waters.

He managed to swim over to the dog and attempt to bring it to shore but then disappeared underwater himself. Ratliff helped to pull Kirwan out of the spring, an action that caused severe burns to his feet. As they waited for the ambulance to arrive, Kirwan muttered about the foolishness of his actions.

"That was stupid. How bad am I? That was a stupid thing I did," he muttered.

Kirwan suffered severe burns to 100% of his body after trying to rescue the dog from the boiling thermal spring. His skin was peeling off and he had lost his hair. As a park visitor attempted to remove one of Kirwan's shoes, they were shocked to find that his skin, which had already begun to peel off, came off with it.

Despite receiving treatment, he passed away the next morning at a Salt Lake City hospital. Moosie also died and the dog's body was never recovered from the pool.