Continuity mistake: When Mr. Freeze's henchman Johnny gets his legs frozen, he is wearing pants and shoes. Later when Johnny is inside a water tank in the Batcave in order to thaw the ice, he has been stripped down to his boxer shorts. While it's possible for Batman to remove Johnny's pants above the freeze-line by cutting them away, he would still have remnants of his pants underneath the ice, but when the ice is thawed, his legs and feet are bare. (00:05:45 - 00:08:05)
Continuity mistake: The broken window pane on the door to the District Attorney's office changes slightly from shot to shot. When first shown, the break in the glass extends all the way up to the letter "L" in the word "law." When the shot changes, the break in the glass is nowhere near the letter "L." Also, the letter "W" in the word "law" is missing entirely, even though the break in the glass suggests a portion of the letter would still be intact if the letters were painted on the glass, as is standard. (00:10:25)
Continuity mistake: The explosion that scars Harvey Dent and creates Two-Face is shown to have scarred and colored him light blue on the entire left half side of his face and neck. However, when he is first shown in the hospital, the parts of the left side of Harvey's face that aren't covered in bandages are still normal, as is his entire neck. (00:19:35)
Continuity mistake: The pothole with the mud that Rupert Thorne's henchman kicks at Harvey Dent appears from nowhere. When the henchman is shown kicking the mud, the pothole is located between the police officer behind the henchman's right shoulder and Harvey's assistant Carlos on the henchman's left. However, in the previous shot, the ground shown between the police officer and Carlos contains no pothole. (00:04:35)
Continuity mistake: When Poison Ivy is introduced in her trademark green costume, she's bare legged. Yet a few shots later, she's suddenly wearing green tights. While she's offscreen for a brief period, there's not enough time between the shots for her to have put them on.