The story, without spoilers
Dom Cobb is the best in a strange and illegal trade. He and his team slip into people's dreams and steal the secrets they keep there. It has cost him his home and his children, and he cannot return to the United States. A powerful businessman named Saito offers him a way back, but the job is the reverse of theft. Instead of taking an idea from someone's mind, Cobb must plant one so deeply that the target believes it was his own.
To do it, Cobb assembles a crew: his long-time point man Arthur, the forger Eames, the chemist Yusuf and a gifted young architecture student, Ariadne, who builds the dream worlds. The deeper they go, the more the rules bend, and the more Cobb's own past keeps appearing where it should not be.
The film explains its rules carefully, with Ariadne learning alongside the audience how dreams can be built, how time stretches in each layer and why dreamers need a way to tell whether they are awake. That patient set-up pays off in the final act, which runs several dream levels at once, each moving at its own speed, and keeps the audience oriented while the stakes rise in all of them.
Behind the scenes
Nolan pitched the idea to Warner Bros. after finishing Insomnia in 2002 and worked on the script for nine or ten years before shooting it. He favoured physical effects wherever he could. For Arthur's weightless fight in a hotel corridor, the production built a hallway set that could rotate a full 360 degrees, so Joseph Gordon-Levitt really was fighting along walls and ceiling.
The film travelled widely. On 15 July 2009 the crew filmed at University College London, whose library, Flaxman Gallery and Gustave Tuck Theatre stood in for a Paris college of architecture. Tangier in Morocco doubled as Mombasa, where Cobb recruits Eames and Yusuf. For the sequence in which a Paris street folds over itself, the team combined location footage with green screen and computer imagery. Hans Zimmer's score was nominated for an Oscar.
Nolan's early idea was a horror story about dream stealers, based on lucid dreaming. Deciding he needed more experience before attempting something so complex, he shelved it and made Batman Begins, The Prestige and The Dark Knight first. Warner Bros. bought the revised treatment in February 2009. Shooting took place in six countries, starting in Tokyo on 19 June and ending in Canada on 22 November, with the $160 million budget split between Warner Bros. and Legendary Pictures.
Why it still matters
Inception showed that an original, idea-heavy film with no franchise behind it could still be a summer event. It earned $839 million worldwide on a $160 million budget and won four Oscars, all for the craft of image and sound, along with a Best Picture nomination.
It also confirmed Nolan, coming off The Dark Knight, as one of the few directors whose name alone could sell a blockbuster. Its spinning top, its layered dream logic and Zimmer's booming brass became widely recognised shorthand, and its ending has been argued over ever since.
Nolan's standing after The Dark Knight helped secure about $100 million in advertising, and the film opened in conventional and IMAX cinemas on 16 July 2010. It finished as the fourth-highest-grossing film of the year. In 2025 the Library of Congress selected it for the National Film Registry, a quick recognition for a film that was then only fifteen years old.