The I-52 is the stuff of shipwreck legend. Possibly the most advanced submarine in the world at the time, Japan's I-52 was sunk in the Atlantic on June 23, 1944, while en route to a rendezvous with a German U-boat. The rendezvous remains a mystery.
It was laden with two tons of gold and two tons of opium, probably for conversion into morphine painkillers. But was it also carrying a secret offer of peace?
Paul Tidwell, an American shipwreck salvager, said Friday he is planning an expedition within a year -- most likely in November or in May 2006 -- to raise the I-52 from the seabed, and perhaps even return the sub to Japan. He didn't know how much the operation will cost.