Curious why people explode after drinking water in Until Dawn? The horror film’s gruesome deaths shocked viewers during a key scene involving a sink and five unlucky characters. As the mystery unraveled, it became clear the water itself carried a dark, supernatural threat tied to the town’s past.
Here’s what caused the deadly reaction in Glore Valley.

Why people exploded after drinking water in Until Dawn explained
In Until Dawn, people explode after drinking water in Glore Valley because lethal contamination taints the supply. Glore Valley, once a mining town, collapsed in a disaster that likely poisoned the underground system. When characters drink the water, their bodies swell and burst. The bathroom scene shows all five main characters detonating after sipping from the sink.
The explosion occurs during a recurring death loop. Clover, Max, Nina, Megan, and Abel die and relive the same night repeatedly. Supernatural forces drive the loop. Wendigos, witches, parasites, and other monsters attack them throughout the cycle. The poisoned water acts as both a physical threat and a symbol of the town’s trauma.
Dr. Alan Hill, played by Peter Stormare, orchestrates the group’s suffering. He watches them through surveillance and studies their reactions. He reveals that Glore Valley turns trauma and fear into physical threats. People with unresolved psychological wounds, like Clover, manifest their inner fears. Clover’s grief over her sister’s disappearance and history of suicide attempts shape the valley’s horrors, including the water’s explosive effect.
The explosions work as both physical horror and psychological metaphor. The poisoned water, tainted by the town’s tragic history and possible supernatural forces, acts as a deadly trigger. It reflects each character’s declining mental and physical condition. In the film’s final act, Clover uses the water against Hill. She puts a drop in his coffee, and he explodes. This breaks the loop and lets the group escape Glore Valley by dawn.