Responding to the Joker's promise to kill someone every day until Batman reveals himself, and the latest attempt on the Mayor, Harvey Dent calls a press conference and announces to the world that he is Batman.
He is taken away to be sentenced as a vigilante. Yet Harvey has a plan to draw out the Joker - knowing that the Joker will not pass up on an attempt to kill Harvey on his way to County. Harvey, in handcuffs, is loaded into an armored van, driven by a mysterious and masked driver.
Soon enough, the Joker shows up with a juggernaught to cause carnage on the city streets. Moving alongside the armored truck, the Joker tries an assortment of weapons to break through the armor plating. Finally, he removes an RPG. Batman moves at speed and takes the force of the explosion.
The Bat Tumbler suffers critical damage. Batman is ejected on a bike while the machine self destructs.
Batman is quickly back in action and ties up the Joker's truck, causing it to flip and crash. The Joker staggers out, taking shots at Batman - wanting to die. Batman cannot do it - he swerves and crashes.
Unconscious, the Joker's men try to open his mask - but take an electric shock. The Joker is suddenly stopped by the mysterious driver - "Gordon's Alive"!!
The Joker is taken to the cells, as Harvey and Rachel are taken home by officers. In interrogation Batman beats the Joker to get answers. The Joker tells him of the next plot - that Harvey and Rachel are tied up - next to timed bombs - and Batman can only save one. Batman races off to rescue Rachel, telling Gordon to find Dent.
As it turns out, the Joker lied and Batman is taken to Dent's location. Dent is soaked in oil after a fall. Batman saves him, but Dent is caught by burning sulphur and badly scarred. Gordon cannot reach rachel in time - and she is killed.
Meanwhile, The Joker goads an officer before escaping from the cell and asking for his phone call -- which triggers a remote bomb in one of his men. The police station explodes, allowing the Joker to pick up Lau and escape.
The dodgy accountant goes public with news that he will soon announce the real identity of Batman. The Joker has found that he needs Batman, so phones a live news channel to tell them that if the accountant is not dead within the hour, he will blow up a hospital. The accountant is put into protective custody.
The Joker gets into Dent's hospital, and manages to turn him. As he leaves, he detonates the buildings - and takes a bus of hostages. The Joker uses one hostage, a newsreader, to annouce his plans - that he owns Gotham and everyone should leave. The city is in chaos.
Meanwhile, Dent goes about cleaning up the dirty cops - and kills Malone.
On two ferries leaving Gotham, the boats stop dead in the water. The Joker announces his grandest plan - that each have a remote detonator. By pressing the detonator, the other ferry will explode - and save their own lives. While one ferry is filled with civilians, the other is filled with hardened criminals.
Batman tells Fox to monitor the sonar-phone device to track the Joker - and finally gets his location.
Batman breaks into the Joker's building, and finds that the hostages are in fact the Joker's men. The SWAT team don't wait and are about to open fire - Batman needs to take out the SWAT teams safely, while making it to the top floor to confront the Joker.
They fight. The Joker gets an upper hand. On the ferries - neither of the crews have pressed the detonator. A huge prisoner takes the detonator and does something 'they should have done 10 minutes ago' ... and throws it out the window. He kneels to pray and others gather around him.
The deadline passes. The Joker is dumbfounded. Batman knocks him off the roof - but sends a grappling hook to catch him before he dies. He is left dangling. The Joker reveals his final plan - that he turned Harvey Dent.
Batman rushes to stop Dent murdering Gordon and his family at the location where Rachel died. He pushes Dent off a high story roof, but falls too. Gordon runs to his side. Dent has died. Batman says that The Joker won in the end and took down the best of them. All of Dent's cases will be reopened. To save the day, Batman must be the fall guy.
As Fox destroys the sonar device, Batman is up and chased by the cops. He is now public enemy number 1 and blamed for Harvey's death. The bat signal is smashed, and only Gordon's family know the truth that he is "The Dark Knight".