Director, writer and producer Christopher Nolan has been working on his sci-fi action film Inception for more than a decade - and it shows. The film has one of the most ingenious plots in years. Leonardo DiCaprio stars as Dom Cobb, a thief who breaks into people's dreams to steal ideas. He is offered redemption by wealthy businessman Saito (Ken Watanabe) if he can pull off the impossible. He has to perform inception - the act of planting, not stealing, an idea - on Saito's business rival Robert Fischer Jnr (Cillian Murphy). DiCaprio gives Cobb a masterful emotional edge, revealing how the action is as much inside him as it is around him. He proves why he has become one of the most sought-after of Hollywood's stars. The A-list supporting cast also exceeds expectations. The complexity of the plot is astounding. The film forces you to engage intellectually, a pleasant relief from the usual mind-numbing summer blockbusters. There are several layers to the storyline, each vital to the plot and intricately woven together. Nolan's ambition is huge, but ultimately pays off. Inception may well be the most philosophical action film since The Matrix, with Nolan questioning reality and the human mind at every turn. When it finishes, your mind and heart will be racing.