The Zodiac Crimes (1) - S2-E37
Continuity mistake: In Commissioner Gordon's office, after Batman uses his handy mini fire extinguisher to extinguish Joker's flaming 2-way spy device, when he walks over to Gordon's desk the mini fire extinguisher is in his left hand, but when it cuts to the closeup as he realises the significance of RAM, the fire extinguisher is suddenly in his raised right hand. (00:06:50)