Where is Poseidon in book 1?

Poseidon is not mentioned by name in the first book of *The Percy Jackson & the Olympians* series, *The Lightning Thief*. However, he is implied to be the source of the storm that causes the trouble for Percy in the beginning of the book.

Here's why:

* The Storm: The book starts with a fierce storm that disrupts Percy's life and sets the events in motion. Storms are associated with Poseidon in Greek mythology.

* Percy's Abilities: Percy later discovers he has control over water, a clear connection to Poseidon.

* Luke's Accusation: Luke accuses Percy of stealing Zeus's lightning bolt, and the fact that Percy is the son of a god suggests that Poseidon could be the culprit.

While Poseidon isn't explicitly named, his presence and involvement are heavily hinted at, laying the groundwork for his more prominent role in later books.