Water

A necessity of life, but in too large of quantities, can be dangerous and deadly. It’s shown a lot across the film.

Whether it’s the first shot and the immense body of water or it’s the flood imagery, or it’s the water coolers scattered around the hotel.

It’s also the snow that encompasses their entire surroundings.

Something naturally occurring, and absolutely necessary to sustain life, but in large quantities, can be absolutely deadly.

It’s also interesting that the first shot of the film is water and Jack’s final bodily appearance is in snow, before the film closes on the photograph.