"Pirate for the Sea" is a biographical film of Captain Paul Watson, the youngest founding member of Greenpeace Canada. He organized early campaigns protesting the killing of seals, whales, and dolphins. Greenpeace ejected him for being too much of an activist. Starting his own organization, the Sea Shepherd Conservation Society, he went on to sink illegal whaling ships, stopped Canadian seal hunts for ten years, permanently halted sealing in British Isles, killing of dolphins on Iki Island, Japan, etc. This documentary witnesses his latest campaigns and explores the personal and environmental history of this controversial marine conservationist.