The man we were introduced to as Ducard (Liam Neeson) is actually Ra's Al Ghul, leader of the League of Shadows. The League's mission is to destroy cities when they become decadent, and they are behind the shadowy dealings going on in Gotham. The League recruited Jonathan "The Scarecrow" Crane (Cillian Murphy) to disperse their hallucinogenic, fear-inducing chemical in the city's water system, and stole Wayne Enterprises' microwave emitter intending to vaporize the water, thus weaponizing the chemical and getting the population of Gotham to kill each other in terror. Ra's reveals that the League had targeted Gotham a generation ago, using a "new method of attack" on economics, and that Thomas Wayne (Linus Roache) had thwarted their efforts. Bruce Wayne/Batman (Christian Bale) and police sergeant James Gordon (Gary Oldman) defeat Ra's and shut down the emitter before too much damage is done. Gordon is promoted to Lueutenant, and in the end sets up an uneasy pseudo-partnership with Batman, calling him in to help catch a psychopath who leaves behind a "calling card" in the form of a Joker playing card.
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