Does this thing come with a manual? British writer-director Christopher Nolan first made a name for himself with the noirish brainteaser Memento (2000), and his growing industry clout as designated auteur of the rebooted Batman franchise (Batman Begins, The Dark Knight) has enabled him to finance ever more elaborate head games on the side (The Prestige and now this summer blockbuster). Inception delivers dazzling special effects and a boatload of stars (Leonardo DiCaprio, Joseph Gordon-Levitt, Ellen Page, Ken Watanabe, Cillian Murphy, Marion Cotillard, Michael Caine), but it sags and eventually buckles under the weight of its complicated premise. DiCaprio and Gordon-Levitt are corporate spies, skilled in the mechanics of dreaming, who assemble a team to get inside the head of industrial scion Murphy. If I tried to explain all the ins and outs of their adventure, reading this capsule would take as long as watching the movie.