In 'The Mountain in the Sea', humanity grapples with the profound implications of a groundbreaking discovery: intelligent octopuses with a culture and language of their own. Set in the near future, the narrative follows Dr. Ha Nguyen, a dedicated marine biologist, as she embarks on an expedition to the sealed Con Dao Archipelago. Funded by the powerful tech corporation DIANIMA, Nguyen delves into the minds of these enigmatic creatures. But as the secrets of cephalopod intelligence begin to unfold, the octopuses' desire for autonomy emerges, setting off a global power struggle that questions the ethics of human intervention and the future of intelligence itself. This debut novel by Ray Nayler combines elements of a thriller, science fiction, and ecological critique to explore consciousness and our environmental impact.