The novel ''Lost Horizon'' was written in 1933 by British author James Hilton (of ''[[Film/GoodbyeMrChips Goodbye, Mr. Chips]]'' fame).

Passengers aboard a small airplane discover that they have been kidnapped by someone posing as their assigned pilot. The plane crashes in the Himalayan mountain range, along the border of China. The dying pilot's last words indicate there is a lamasery nearby at Shangri-La and they will find help there. The passengers go to the lamasery and are offered shelter there. Then mysteries start to unfold: the passengers want to leave but but are unable to, and it becomes clear that time passes differently here.

It was [[Film/LostHorizon filmed by Frank Capra in 1937]], and again in 1973 as a spectacular star-studded musical flop.

Not to be confused with the power metal band with the same name.

!!This novel provides examples of:
* AdaptationNameChange: The book's Hugh Conway became Robert Conway in the 1937 film and Richard Conway in the 1973 film.
* {{Aesop}}: The novel warns of an impending World War [[note]]And it was written in between WW-I and WW-II in Real Life...[[/note]].
* BilingualBonus: "Shangri-La" means "Shang Mountain Pass" in Tibetan.
* TheChosenOne: Conway was specially selected to go to Shangri-La, and the other passengers were considered wonderful, accidental additions to the lamasery who all (excepting Mallinson) found reasons to be happy there.
* FramingDevice: The main story is being told among two former schoolmates of Conway, one of whom got his story from Conway himself.
* HiddenElfVillage: Shangri-La is a deliberately inaccessible place where carefully selected candidates are expected to isolate themselves from a world without hope.
* HurtingHero: Conway, the protagonist, saw very disturbing stuff during his service in UsefulNotes/WorldWarI, and he never got quite over it.
* InterfaithSmoothie: According to the High Lama, the lamasery was originally Buddhist, then Father Perrault converted it to Christianity, but in his later years he embraced not only Buddhism but some elements of Hinduism as well.
* LiteraryAgentHypothesis: The book is written by someone who heard the story from Conrad.
* MacGuffinLocation: Shangri-La
* MayDecemberRomance: Mallinson and Lo-Tsen... if Perrault is telling the truth of course.
* MightyWhitey: Featuring a modern MightyWhitey in the 1930s, when the old-fashioned version was still in vogue. The mostly Chinese and Tibetan monks there prove themselves to be wise, intelligent, competent, and well-rounded characters. However, the white Conway turns out to be better at being a monk than the best of the Tibetans, and it turns out that the founder and leader of the monastery is a European who arrived in the 15th century.
* NoImmortalInertia: It is heavily implied that [[spoiler: Lo-Tsen lost her youth almost as soon as she left Shangri-La]].
* OrganizationWithUnlimitedFunding: The monastery.
* RapidAging: This may be Lo-Tsen's fate as explained in NoImmortalInertia.
* SecretIdentity: Barnard is really Chalmers Bryant and the High Lama might really be [[spoiler:Father Perrault]].
* TheShangriLa: The novel is the trope namer, due to Conway's efforts to get back at any price.
* UnreliableNarrator: Mallinson points out to Conway (and the reader) that the High Lama might be just lying.