The Lafayette O'Leary series by Keith Laumer is a humorous fantasy trilogy consisting of The Time Bender (1965), The World Shuffler (1970), and The Shape Changer (1972).
Lafayette O'Leary is an ordinary guy with a boring job, who dreams of a life full of adventure and fantasy. Literally. He's studying techniques for controlling his own dreams. And one day, he succeeds, and finds himself dreaming of a fantasy kingdom called Artesia. He even has a limited ability to manipulate the dream, as long as he doesn't violate the internal dream-logic—for example, he can't make money appear in his hand, but can make it appear in his pocket as long as he hasn't already checked the contents of that pocket.
However, when he "wakes up" back in our world at the Ladies' changing room in the local Y, and is promptly arrested, he realizes that travel in Artesia translates to travel in our world, somehow—maybe Artesia isn't just a dream! Which makes his reality-changing powers in Artesia all the more inexplicable. And if it isn't a dream, coming from his subconscious, why do so many elements of the world seem vaguely familiar?
In The World Shuffler, O'Leary has settled in as a respected citizen of Artesia, when he suddenly finds himself transported to another world, Melange, which is full of people who look very much like the people of Artesia, but who are very different.
In The Shape Changer, O'Leary discovers a strange artifact which allows him to swap bodies with people.
The three books have been collected in an omnibus under the name The Universe Twister.
Tropes in these books:
- Alternate Self: In The World Shuffler, when O'Leary is transported from Artesia to the parallel world of Melange, he encounters several folks who are alternate versions. The princess Adoreanne, who rules Artesia, is now a barmaid of loose morals named Swinehilde, and her consort, the Count Alain, is now a jealous barkeep named Hulk. His wife is now a noblewoman, Lady Andragorre, and worst of all, there appear to be several Lafayette O'Learys, from several different worlds, all working at cross-purposes.
- Bird People: In The Shape Changer, the second person O'Leary experiences a "Freaky Friday" Flip with is a bird-like humanoid from a nearby universe.
- Coincidental Accidental Disguise: In The Time Bender, when O'Leary first appears in the kingdom of Artesia, he uses his newfound powers to create what he thinks is an appropriate set of clothing for what seems to be a rather medieval setting. Unfortunately, the result looks exactly like the legendary figure known as the Phantom Highwayman, and ends up terrifying people.
- Dinosaurs Are Dragons: In The Time Bender, the dragon owned by the Giant Lod, who is threatening the kingdom of Artesia, turns out to be a dinosaur. In fact, there's two: a friendly Iguanodon, and a much more hostile T-Rex.
- Damsel in Distress: In The Time Bender, Princess Adoreanne is mysteriously kidnapped, and both O'Leary and Count Alain vow to rescue her—but Alain is convinced that O'Leary is the kidnapper.
- Dimensional Traveler: The protagonist has the ability to travel to feudal/magical alternate Earths.
- "Freaky Friday" Flip: In The Shape Changer, O'Leary finds himself swapping bodies with a series of strange people for reasons he doesn't entirely understand. It starts with a local thief named Zorro, but soon after, he finds himself swapping with people from other worlds. It's an unusual variant where the minds stay where they were, and the bodies change places.
- The Good Kingdom: Artesia is a small, once-happy kingdom, threatened by a outside conqueror known as Lod. While Lod isn't exactly a representative of a mighty Empire—he's closer to a bandit than an Emperor—Artesia is small enough that he remains a serious threat. Especially since he has his own dragon.
- Guardian of the Multiverse: The mysterious agency known as "Central" is a sort of cross between this and Time Police. Charged with keeping the multiverse running properly, and sorting out cross-reality entanglements, their somewhat hidebound bureaucracy tends to make them less than completely efficient at their jobs, often leaving O'Leary in the lurch.
- Lost Orphaned Royalty: In The Time Bender, Lafayette O'Leary turns out to be the missing heir to the throne of Artesia. However, in the event, he doesn't want the crown, and abdicates in favor of Princess Adoreanne.
- The Multiverse: The core premise of the series. In The Time Bender, O'Leary finds himself transported to the kingdom of Artesia in an alternate universe. In The World Shuffler, he is transported to another world, Melange, which is a close parallel to Artesia, and even has alternate versions of several of the people he knows from Artesia, including his wife.
- Obstructive Bureaucrat: O'Leary has the phone number for the mysterious agency known as "Central", whose job it is to keep the multiverse running properly, but whenever he calls with a spacetime-breaking emergency, he inevitably gets connected to some paper-pusher who refuses to believe him, and doesn't want to get involved.
- Princesses Rule: When Princess Adoreanne ascends to the throne of Artesia, she remains a princess for reasons which are never explained, but presumably have something to do with the fact that she's still young and beautiful and subject to various common "princess" tropes.
- Sufficiently Advanced Technology: The mysterious agency known as "Central" has this in spades. Their technology seems to give them near-complete control of spacetime. If they weren't such a hidebound bureaucracy, they could easily solve all O'Leary's problems, and there wouldn't be much plot left. Nicodaeus, the court wizard for the kingdom of Artesia is actually an agent of Central, and, unlike O'Leary, lacks any real magical powers.
- Talking to Themself: In The World Shuffler, at one point, O'Leary is "sick, freezing, starving, hung-over, and dyspeptic", not to mention lost and frustrated, and he begins talking to himself. And answering himself. He acknowledges—to himself—that it's a sign of insanity, but responds "Poof, what's a little touch of schizophrenia, among all my other ailments?"
- Transformation Trinket: In The Shape Changer, O'Leary receives a device just called a "Mark III" from his old friend, the semi-retired highwayman Red Bull, which changes his shape to that of a sneak thief called Zorro, and he promptly ends up getting arrested.