The Poseidon Project is a 2013 documentary film about the search for the lost Royal Navy submarine HMS Poseidon. The submarine sank after a collision off the coast of China in 1931. It was widely assumed to be still present in the Bohai Sea, 20 miles off the city of Weihai in China's Shandong Province until American author and scuba diver Steven Schwankert discovered that she had been salvaged by a Chinese salvage team in 1972. Schwankert's work and the history of the submarine and its crew is the subject of The Poseidon Project. The film was directed by British brothers Arthur Jones (film director) and Luther Jones.