An incredible film. You must see it.
Don't expect to get it in one viewing. This is not a problem as you will want to see it more than once. Chris Nolan has a thing about the concept of time and this film is an intricate exploration of dreams and the distortion of time. This is further explored by Nolan in Interstellar, Tenet and Dunkirk. The sound track (Zimmerman) is integral to your emotional response to it. Don't stress if at times you feel confused or a little lost, just enjoy the ride.
The 20th century had Hitchcock; the 21st has Nolan.
The premise is that one can share dreams and if done right, a person can implant ideas into another while sharing the dream. DiCaprio is the lead who has mastered the idea of raiding people's subconscious in the dream state to manipulate their ideas. He is hired by an industrialist who want him to change the corporate direction of a competitor. In return, the industrialist can remove the untrue murder arrest warrant for DiCapro to allow him to return to the United States to see his children. DiCaprio's dead wife haunts his subconscious and interferes with his job during the shared dreams and put him and his team at grave risk.
There are little homages through out the film. The nicest one is near the end where Nolan does a little homage to the penultimate scene in 2001 a Space Odyssey where Dave Bowman is an old man in the hospital bed in the star.
Watch this film over and over again.