Inception is a 2010 science fiction action heist film, written, co-produced, and directed by Christopher Nolan. The film features an ensemble cast starring Leonardo DiCaprio, Ken Watanabe, Joseph Gordon-Levitt, Marion Cotillard, Ellen Page, Tom Hardy, Cillian Murphy, Dileep Rao, Tom Berenger, and Michael Caine. DiCaprio plays Dom Cobb, a specialized spy or corporate espionage thief. His work consists of secretly extracting valuable commercial information from the unconscious mind of his targets while they are asleep and dreaming. Unable to visit his children, Cobb is offered a chance to regain his old life in exchange for an almost impossible task: "inception", the planting of an idea into a target's subconscious.

Development began roughly nine years before Inception was released. In 2001, Nolan wrote an 80-page treatment about dream-stealers, presenting the idea to Warner Bros. The story was originally envisioned as a horror film, inspired by concepts of lucid dreaming and dream incubation. Feeling he needed to have more experience with large-scale films, Nolan opted to work on Batman Begins, The Prestige, and The Dark Knight. He spent six months polishing up the script for Inception before Warner Bros. purchased it in February 2009. Filming spanned six countries and four continents, beginning in Tokyo on June 19, 2009, and finishing in Canada in late November of the same year.

Inception was officially budgeted at $160 million, a cost that was split between Warner Bros. and Legendary Pictures. Nolan's reputation and success with The Dark Knight helped secure the film's $100 million in advertising expenditure. Inception premiered in London on July 8, 2010, and was released in both conventional and IMAX theaters on July 14, 2010. A box office success, the film grossed over $21 million on its opening day, with an opening weekend gross of $62.7 million. Overall, Inception has grossed over $800 million worldwide and is currently one of the highest-grossing films of all time. In addition to strong box office results, Inception has also grossed $68,644,403 in DVD-sales.

Inception received wide critical acclaim, with numerous critics praising it for its originality, cast, score, and visual effects. The film received eight Academy Award nominations, including Best Picture and Best Original Screenplay, and won four awards for Best Sound Editing, Best Sound, Best Cinematography, and Best Visual Effects.

Dom Cobb (Leonardo DiCaprio) and his partner Arthur (Joseph Gordon-Levitt) perform an illegal corporate espionage by entering the subconscious minds of their targets, using two-level "dream within a dream" strategies to "extract" valuable information. Each of the "extractors" carries a "totem", a personalized small object whose behavior is unpredictable to anyone except its owner, to determine whether they are in another person's dream. Cobb's totem is a spinning top which perpetually spins in the dream state. Cobb struggles with memories of his dead wife, Mal (Marion Cotillard), who manifests within his dreams and tries to sabotage his efforts.

Cobb is approached by the wealthy Mr. Saito (Ken Watanabe), Cobb's last extraction target, asking him and his team to perform the act of "inception", planting an idea within the person's subconscious mind. Saito wishes to break up the vast energy empire of his competitor, the ailing Maurice Fischer (Pete Postlethwaite), by suggesting this idea to his son Robert Fischer (Cillian Murphy) who will inherit the empire when his father dies. Should Cobb succeed, Saito promises to use his influence to clear Cobb of the murder charges for his wife's death, allowing Cobb to re-enter the United States and reunite with his children. Cobb assembles his team: Eames (Tom Hardy), an identity forger; Yusuf (Dileep Rao), a chemist who concocts the powerful sedative needed to stabilize the layers of the shared dream; and Ariadne (Ellen Page), a young student architect tasked with designing the labyrinth of the dream landscapes. Saito insists on joining the team as an observer and to assure the job is completed. While planning the inception, Ariadne learns of the guilt Cobb struggles with from Mal's suicide and his separation from his children when he fled the country as a fugitive.

The job is set into motion when Maurice Fischer dies and his son accompanies his father's body from Sydney to Los Angeles. During the flight, Cobb sedates Fischer, and the team bring him into a three-level shared dream. At each stage, the member of the team who is "creating" the dream remains while the other team members fall asleep within the dream to travel further down into Fischer's subconscious. The dreamers will then ride a synchronized system of "kicks" (a car diving off a bridge, a fall between hotel rooms, and a collapsing building) back up the levels to wake up to reality. In the first level, Yusuf's dream of a rainy city, the team successfully abducts Fischer, but the team is attacked by Fischer's militarized subconscious projections, which have been trained to hunt and kill extractors. Saito is mortally wounded during the shoot-out, but due to the strength of Yusuf's sedative, dying in the dream will send them into limbo, a deep subconscious level where they may lose their grip on reality and be trapped indefinitely.

Eames takes the appearance of Fischer's godfather Peter Browning (Tom Berenger) to suggest that he reconsider his opinion of his father's will. Yusuf remains on the first level driving a van through the streets, while the remaining characters enter Arthur's dream, taking place in a corporate hotel. Cobb turns Fischer against Browning and persuades him to join the team as Arthur runs point, and they descend to the third dream level, a snowy mountain fortress dreamed by Eames, which Fischer is told represents Browning's subconscious. Yusuf's evasive driving on the first level manifests as distorted gravity effects on the second, forcing Arthur to improvise a kick using an elevator shaft, and an avalanche on the third.

Saito succumbs to his wounds, and Cobb's projection of Mal sabotages the plan by shooting Fischer dead. Cobb and Ariadne elect to enter limbo to find Fischer and Saito. There, Cobb confronts his projection of Mal, who tries to convince him to stay with her and his kids in limbo. Cobb refuses and confesses that he was responsible for Mal's suicide: to help her escape from limbo during a shared dream experience, he inspired in her the idea that her world wasn't real. Once she had returned to reality, she became convinced that she was still dreaming and needed to die in order to wake up. Through his confession, Cobb attains catharsis and chooses to remain in limbo to search for Saito; Eames defibrillates Fischer to bring him back up to the third-level mountain fortress, where he enters a safe room and discovers and accepts the idea to split up his father's business empire.

Leaving Cobb behind, the team members escape by riding the kicks back up the levels of the dream. Cobb eventually finds an elderly Saito who has been waiting in limbo for decades in dream time (just a few hours in real time), and the two help each other to remember their arrangement. The team awakens on the flight; Saito arranges for Cobb to get through U.S. customs, and he goes home to reunite with his children. Cobb uses his spinning top to test reality but is distracted by his children before he can see the result.