Ethan Jackson, a father plagued by his past sins – stealing from his wife’s sister and an unforgivable violent outburst – seeks to mend his fractured family. He plans a weekend getaway to Muskoka with his wife, Ava, and their son, Noah, an eight-year-old with a curious fascination for fire. But as they arrive at a desolate hotel, an impending brutal snowstorm threatens more than just their weekend plans.

The hotel, run by Chen, a homely woman with deeply rooted religious beliefs, becomes their eerie sanctuary. Chen's fixation on protection and divine intervention immediately sets an unsettling tone. As the family settles in, Noah's fascination with fire takes a dangerous turn. He narrowly escapes harm near a fireplace, an incident that Chen ominously attributes to the divine. Chen suddenly becomes increasingly interested by the Jackson family and Ethan’s pursuit to fix his family unit. She even Googles them.

Trouble escalates when both Ava and Noah start exhibiting bizarre symptoms – their bodies begin to slowly blister, becoming feverish. Ethan, desperate to help his family, finds no solace in Chen's cryptic religious ramblings and her unsettling conviction in the demonic entity Yan Wang, the King of Hell. After all, he’s a hard atheist.

Amidst the growing horror, Noah asks Ethan to read him his favourite book, "The Brave Little Builder". Ethan recites in agony: "Remember, Peter," Father had warned, "fire is a tricky friend. It warms our home and gives us light so were not afraid, but if were not careful, it can also burn..."