Revealing mistake: Harvey Dent and the mayor argue in Dent's office which has an unusual semicircular shape. In the next scene, Alfred uses the telephone in Wayne Manor, and you can see that it's the same room, just with different furniture and dressings. (00:56:10)
Revealing mistake: When the shields of the Batmobile are engaged, the metal plates come from nowhere. There isn't a place for them to come from or go to when taken off. And if you watch carefully, the shields coming from the sides of the Batmobile come out of thin air. (01:09:10)
Revealing mistake: After the Batmobile's pair of machine guns riddles a straight line of bullet holes through a bay door of Axis Chemicals, it drives in and eventually goes on to blow up the plant. It might seem like the bullet holes themselves would weaken the bay door enough for the Batmobile to push through. But instead - as the bay door falls to the ground - notice how a ready-made seam splits apart directly above the line of bullet holes. (01:34:15)
Revealing mistake: Right after Joker falls off the top of the cathedral, Batman and Vicky fall too and we catch them three times before Batman's grapple digs into the stone. On the second and third time you can actually notice Vicky's face expression doesn't look one bit scared, so you know they're not falling. You can also see there's a screen in the background. (01:58:40)
Revealing mistake: At the end when they show the Joker dead on the pavement after he fell, look closely during the first few seconds of the shot and you'll see him blink twice. (01:59:05)
Revealing mistake: When the Joker is having the party with all the balloons, Vicky Vale tries to escape from the gas by getting into a car. If you look at the back window while she is driving off, the window is rolled down, which would have led to her death, not to mention motor vehicles are not air tight to begin with.
Revealing mistake: When Jack and his goons are breaking into Axis Chemicals, there's a scene where they're cutting the lock off of a safe. When the safe door is opened, you can clearly see that there is no locking mechanism in the side of the door.
Revealing mistake: When the Joker is in the basement getting surgery, he walks up the stairs laughing and when you see the side of his body before the end of the scene, if you look closely, you can see that his face is still normal Caucasian tone.
Revealing mistake: When the Joker first appears, you can see a purple splodge on the left side of his neck.
Revealing mistake: When Vicki is driving the car Knox jumps on, you can see it's a stunt driver in the wide shots.
Revealing mistake: In the beginning, the first shot we see of Batman (a shot from above where he turns and walks into a doorway, casting a shadow behind him) is quite obviously animated. He literally looks like a cartoon... because he is one in this shot for some reason.
Revealing mistake: When Batman drives the Batmobile into the Axis Chemicals factory, watch closely when he slams through the first gate - you can see the gate is swaying and starting to open before the batmobile hits it, indicating it wasn't really closed and was left unlocked and partially open to make it easier for the stunt-driver to drive the Batmobile through it.
Revealing mistake: When the Batjet crashes, if you pay close attention to the scale of the jet, cars and buildings in relation to the scale of the fire and explosions, it is very clear that this scene was created with models.
Revealing mistake: When the reporter dies on air, her face is contorted into the Joker's face. When the camera is in closeup on her face, the "dead" woman's bottom lip moves.
Revealing mistake: When Jack falls into the chemical vat it's obvious the vat is quite shallow as he doesn't actually sink into the chemicals but instead just kind of lands and then sits there as liquid splashes out around him. To top it off, the subsequent shot of him disappearing into the chemicals is reversed as several bubbles can be seen 'unpopping' and growing smaller.
Revealing mistake: In the film's ending shot, the sky can be seen to flutter as the camera pans up, revealing a backdrop.
Revealing mistake: When Batman fires rockets at the Joker, none come out, instead a sound effect is used which cuts to explosions on the road where Joker stands.
Revealing mistake: In an overhead shot, just before Jack Napier falls into the vat of chemicals, you can see that it is a stunt double, as he has significantly less hair on the top of his head than Jack Nicholson.
Answer: He could have looked up her address in the phone book. Just before Bruce arrives at Vikki's apartment, Joker asks Bob the Goon for - a phone book. Also he could have been tailing Bruce and found her apartment that way, after all he does show up not long after Bruce does.
Alan Keddie