Watch The Deep Dark Sea (2025) : Full Movie Online Free Sanctuaries in the Dark, a documentary about the deep sea. Sixgill sharks, ghost sharks (chimaeras), big-finned squid (Magnapinna), telescope octopuses, siphonophores (Bathyphysa), drifting jellyfish, and the silent abyss cleaning team: sea cucumbers and giant isopods. Visit hydrothermal vents, where chemosynthetic microbes feed oases of life with giant tubeworms (Riftia pachyptila) and Pompeii worms; glide over coral gardens of seamounts and ancient schools of sponges; watch as wooden and whale waterfalls transform darkness into cities of life; and pause at octopus farms, heated by gentle filtrations. This film features only real footage of deep-sea creatures, filmed by NOAA's incredible ocean exploration institutes and the Schmidt Oceanographic Institute.