The video shows a large, prehistoric fish swimming in the ocean. The fish has a long, pointed tail and a row of sharp teeth along its jaw. It is surrounded by a school of smaller fish that are swimming around it. The water is a deep blue color, and the lighting suggests that it is daytime. The prehistoric fish moves slowly and gracefully through the water, with its fins and tail propelling it forward. The smaller fish seem to be following the larger fish, possibly as a form of protection or companionship.