Joe Lane 
Last Out From Roaring Water Bay [EPUB ebook] 

Shackleton Speed steals the reconnaissance camera from the remains of a WWII Spitfire he had unearthed with his metal detector. Now two friends are dead and their killers were after him. The connection is the developed photographs from the old celluloid film. They show the I-52, a Japanese submarine, somewhere off the British coast when history records the I-52 was sunk in the Atlantic while carrying gold to the Third Reich. Speed sets out for revenge and to expose those responsible. The trail leads him to Southern Ireland and Roaring Water Bay where he uncovers the hidden horrors of WWII.