 Crabb disappeared after a dive on the "Sverdlov"s sister ship, "Ordzhonikidze" in Portsmouth harbour in 1956, but 14 months later a body in a frogman suit was found floating off Pilsey Island.The body was mutilated and identification by relatives proved difficult.Knowles knew that Crabb had two prominent scars on his left leg; having failed to find any scars on the corpse he refused to identify it as Crabb's.