Seven (Dreams, #8)

After destroying a megalomaniac computer, Pinkerton leaves Lingstrom on the river cruiser Spinifex with Alexis. When Alexis disappears while in the company of a mystery girl, Codeen, Pinkerton goes in search with Lana, the captain's daughter to the Grange Mountains. Inside the mountains he finds another world and a mystery that takes him back to the creation of the universe.