U-330 receives a triple-encoded message with instructions to collect two prisoners from a vessel located off the Icelandic coast and transport them to the base at Brest--and a British submarine commander, Sutherland, and a Norwegian academic, Professor Bjornar Grimstad, are taken on board. Contact between the prisoners and Lorenz has been forbidden, and it transpires that this special mission has been ordered by an unknown source, high up in the...