After saving the emperor's life in Rome, Marcus & his comrades have been sent across the sea to the wealthy, corrupt Greek metropolis
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Alfred sets off in his submarine up the dark & wilful St Lawrence River. With Hollie & Seaweed, his dog & seagull crew, Alfred follows the route of Jacques Cartier, nearly five hundred years before them, as they sail down the Strait of Belle Isle into the largest river mouth in the world.