SPOILER ALERT: the following article contains massive spoilers, including the ending. If you have not yet seen the movie, proceed at your own risk, or better, come back to this article later!
Batman raises the stakes in his war on crime. With the help of Lt. Jim Gordon and District Attorney Harvey Dent, Batman sets out to dismantle the remaining criminal organizations that plague the streets. The partnership proves to be effective, but they soon find themselves prey to a reign of chaos unleashed by a rising criminal mastermind known to the terrified citizens of Gotham as the Joker.
SPOILERS AHEAD
The Dark Knight Plot Summary and Synopsis
A gang of criminals rob a Gotham City mob bank; the Joker manipulates them into murdering each other for a higher share until only he remains, escaping with the money.
Batman, District Attorney Harvey Dent and Lieutenant Jim Gordon form an alliance to rid Gotham of organized crime.
Bruce Wayne is impressed with Dent’s idealism and offers to support his career; he believes that, with Dent as Gotham’s protector, he can give up being Batman and lead a normal life with Rachel Dawes—even though she and Dent are dating.
Mob bosses Sal Maroni, Gambol, and the Chechen hold a videoconference with their corrupt accountant, Lau, who has hidden their funds for safekeeping and fled to Hong Kong.
The Joker warns them that Batman is unhindered by the law, and offers to kill him in exchange for half their money. After Joker kills Gambol and takes over his gang, the mob accepts his offer.
Batman finds Lau and brings him back to Gotham to testify, allowing Dent to apprehend the entire mob. The Joker threatens a string of murders unless Batman reveals his identity, and starts by killing Police Commissioner Gillian B. Loeb and Judge Surrillo.
He targets the mayor but Gordon sacrifices himself to stop the assassination. Rachel is the next target.
Bruce plans to reveal his identity to stop the murders but Dent, refusing to allow him to do so, announces that he is Batman instead. Dent is taken into custody and the Joker attacks the convoy. Batman and Gordon, who faked his death, rescue Dent and apprehend the Joker. Rachel and Dent are kidnapped and the Joker reveals that they are in separate locations rigged with explosives.
Batman races to save Rachel while Gordon attempts to rescue Dent. Batman realizes too late that the Joker sent him to Dent’s location instead. Both buildings explode, killing Rachel and disfiguring half of Dent’s face. The Joker escapes with Lau, whom he kills along with the Chechen.
Coleman Reese, an accountant at Wayne Enterprises, deduces that Bruce is Batman and tries to go public with the information. Not wanting Reese’s revelation to interfere with his plans, the Joker threatens to destroy a hospital unless Reese is killed within the hour.
The Joker convinces a disillusioned Dent to seek revenge for Rachel’s death, then destroys the hospital. Dent goes on a killing spree as the vigilante Two-Face, targeting those he holds responsible for Rachel’s death.
After announcing Gotham will be subject to his rule come nightfall, the Joker rigs two ferries with explosives, one containing civilians and the other prisoners.
He threatens to blow them both up but will let one ferry live if its passengers blow up the other. Batman finds the Joker by exploiting the sonar capabilities of all the phones in the city. The civilians and the prisoners refuse to kill each other, proving that Gotham still has hope in good.
As SWAT takes the Joker into custody, he gloats that Gotham’s citizens will lose hope once the admired Dent’s rampage becomes public knowledge.
Gordon and Batman encounter Two-Face, who has held Gordon’s family as hostages. Two-Face shoots Batman and threatens to kill Gordon’s son, claiming that Gordon’s negligence is responsible for Rachel’s death.
Batman tackles Two-Face off the building to his death. He persuades Gordon to hold him responsible for Dent’s killing spree to preserve Dent’s heroic image, believing Dent is the hero Gotham needs right now.
The Dark Knight Ending
Dent is hailed as a hero and the police launch a manhunt for Batman, with Gordon unwillingly destroying the Bat-signal.
Source: Wikipedia (CC BY-SA 3.0).