From the Depths
(Reklamlänk)
The titular short story from the British Library Tales of the Weird collection From the Depths. A Swedish freighter is on a special mission to locate and survey a number of wrecks after the First World War. The first on their list was torpedoed exactly one year to the day and this proves to be no coincidence when the commander is suddenly tormented by an impossible Morse Code transmission from beyond the grave.
