Watch Online Free on Watchseries. One hundred meters down, in the pitch-black darkness of some of the world’s most treacherous waters, a twenty-strong team of elite divers use cutting-edge equipment and revolutionary techniques to create some of the most stunning underwater visuals captured on film. Their mission; to chronicle and pay tribute to the countless war-time wrecks at the bottom of a sea which has never known peace and is, even now, being contested by the world’s superpowers.