Leonardo Dicaprio thinks 'Inception' is like a "domino".

The 35-year-old actor - who plays the leader of a gang of dream thieves in director Christopher Nolan's latest film - loves the ideas behind the sci-fi movie and thinks the clever plot will give audiences something to reflect on afterwards.

He said: "It's a highly ambitious film and it works on four different states of the subconscious mind. It's like a domino with each one affecting the other.

"It's Chris Nolan delving into dream psychoanalysis and also making a high-octane, action-0filled, surreal film."

The 'Shutter Island' star also admitted filming the movie required a lot of "detective work" as he had no idea what it was actually about.

He explained in an interview with the Daily Mirror newspaper: "Chris wrote the entire thing and it all made sense to him, although it didn't make much sense to us when we were doing it.

"We had to do a ton of detective work to try to figure out what the movie was all about and what we were doing from day to day."