No, you’re not looking at someone in the process of transforming into The Hulk, but rather an interesting science experiment. In this video, a scientist from the University of Toronto, Canada – known as NurdRage on YouTube – places his hand in a jar of hot ice (molten sodium acetate) so it crystallizes around his fingers. Seconds later, the man’s fingers are coated in a thick layer of ice. But instead of being cold, the scientist explains that his hand is actually quite warm, ‘like a hot bath’. Continue reading for a video on how to make hot ice at home.

According to NurdRage, “Normally solid sodium acetate was melted into a liquid that was then supercooled to below its melting point. In this state, adding nucleation sites, like the crystals on my hand, rapidly causes the rest of the sodium acetate to crystallize.”