It gets absolutely ridiculous and it needs a nearly three-hour runtime just to sort it all out.
Instead, it introduces a bunch of new plot details, like sea gods and pirate lords and gets bogged down in every character trying to double cross every other.
Pirates of the Caribbean: Dead Man’s Chest is a fine enough film.
It sets up a solid trilogy finale with pirates fighting for their very existence as the East India Company has control over Davy Jones.