Summerhill is a dog with a problem: he isn't exactly sure who he is. Living alone in a desolate world as its only inhabitant, he has no memories of his previous life-only the tantalizing clue that the answers he seeks may lie with a mysterious woman named Katherine, the hostess on a cruise ship that sails between dimensions. But Katherine has problems of her own, and if Summerhill wants her help in unlocking the secrets of his past, he'll have to help Katherine deal with hers. Together, the two will travel to different worlds, different times, and different universes in a journey where the possible and impossible can be tough to separate, and where the rules of reality can change as easily as weather.