The film picks up a plot thread from it's predecessor; Bruce Wayne's long time friend and Gotham DA Harvey Dent has been critically injured during an attempt on his life by the mob. Batman sets out on a revenge mission, hunting down the gang members. Meanwhile, a second attempt on Harvey's life is made at Gotham General Hospital; however, he dissapears afterwards.
At Wayne Industries, a researched named Edward Nygma attempts to create various nefarious devices, and one day gets the chance to present one to his hero; Bruce Wayne. However, Wayne notes the dodginess of some of his products and dismisses him. Nygma is subsequently fired by his supervisor.
Nygma returns to his lab later that night, where he murders his supervisor and then hatches a revenge plot against Wayne. Meanwhile, several criminals are brutally murdered, purportedly at the hands of the vigilante 'Two-Face.' Batman and Alfred investigate.
During an attendance to the circus, Wayne witnesses a performance by the acrobatic troop known as the Flying Graysons. However, the circus owner, having not payed protection money to mob boss Tony Zucco, is in dire straights. Zucco's men sabotage the equipment, causing all but the youngest Grayson, Dick, to fall to their death.
While Grayson undergoes a psychological evaluation, Wayne meets Dr. Chase Meridan. He also decides to take Dick under his wing and adopt him, sharing the pain as his own parents where murdered when he was just a child.
Nygma reshapes his image and becomes the criminal mastermind known as the Riddler; he uses a game of riddles to lure police to a warehouse owned by Wayne Enterprises before detonating a bomb hidden within. Batman determines that he must stop the Riddler.
Bruce convinces Dick not to seek revenge, showing him another way of venting his rage; to become his sidekick, Robin. Meanwhile, the Riddler is confronted by 'Two-Face,' who is revealed to be Harvey Dent. Blaming Batman for his disfigurement, he plans to assist Riddler in killing him.
Returning home from a date with Chase Meridan, Bruce finds that Wayne Manor has been trashed by the Riddler and Alfred injured. He also learns that Dick has been kidnapped, as is Chase.
Batman makes his way to the Riddler's secret island, where he finds that Two-Face plans to have Robin betray Batman by murdering Zucco. Zucco takes advantage of the situation and shoots Two-Face before turning to Batman and Robin, however, the wounded Two-Face kills him before dying.
The two then climb to the girders over a pit to confront the Riddler; in the ensuing scuffle the villain falls to his death. Batman then rescues Chase before she can be killed by the Riddler's final bomb.
Eric Bana - Bruce Wayne/The Batman
Logan Lerman - Dick Grayson/Robin
Geoffrey Rush - Alfred Pennyworth
Bryan Cranston - Comissioner James Gordon
Billy Dee Williams - Lucius Fox
Scarlett Johansson - Dr. Chase Meridan
Michael C. Hall - Edward Nygma/The Riddler
Michael Fassbender - Harvey Dent/Two-Face