Greek sea gods conform to a single type: that of Homer's "halios geron" or Old Man of the Sea: Nereus, Proteus, Glaucus and Phorkys. These sea gods are not as powerful as Poseidon, the main god of the oceans and seas. Each one is a shape-shifter, a prophet, and the father of either radiantly beautiful nymphs or hideous monsters (or both, in the case of Phorkys). Nymphs and monsters blur, for Hesiod relates that Phorcys was wed to the "beautiful-cheeked" Ceto, whose name is merely the feminine of the monstrous Cetus, to whom Andromeda was due to be sacrificed. Each appearance in myth
The God Beneath the Sea throws Hephaestus for a second time from Olympus. Hephaestus lands on the isle of Lemnos and is nursed to health by the locals. He returns to Olympus and is greeted by Hermes. At the novel's conclusion, Autolycus muses in a letter to his daughter that his grandson Odysseus may one day visit the new city of Troy. Blishen and Garfield began work on "The God Beneath the Sea" after discovering that Greek mythology had had similar impacts on them as primary school children. In Blishen's words, "these stories seemed to illuminate, to make clear, what was going on around me