Set in the universe of the 'Daomu Biji' (The Lost Tomb) series, 'The Tomb of Sea' follows Li Cu, an ordinary high school student who is kidnapped and forced into a dangerous expedition into the Badain Jaran Desert. He is coerced by the enigmatic and legendary Wu Xie, who has spent years orchestrating a complex plan to dismantle the ancient and powerful organization known as the Wang Family. As Li Cu navigates the treacherous desert and the mysterious ruins hidden beneath the sands, he discovers that he holds a key piece of information carved into his own back. The series explores themes of legacy, sacrifice, and the heavy burden of history as Wu Xie maneuvers his pawns to end a centuries-old conspiracy that threatens the balance of the world.