Plot hole: Fletcher and Warren steal what they think is the right paper, so Godber can study it before he sits the exam. They are adamant that he has a very short time to go through it as they have to put it back before anyone misses it. After Godber refuses to cheat by reading it, Fletcher berates him, throws the paper on the cell floor, and storms out. What happened to replacing the stolen exam paper?
Continuity mistake: Interior shots of Ivy's cafe show a window in the back wall of the kitchen, visible through the door to the dining area. Exterior shots of the building show only a plain stone wall where the window should be.
Moving House - S3-E1
Revealing mistake: At the beginning when Frank is directing the vans, we see that one gets its windscreen broken by a ladder from another van. However, the glass breaks just before the ladder touches it.
The Illusion of the Deadly Conglomerate - S1-E18
Continuity mistake: Blake tosses the trick card, and it lands on the lower right side of the target. When Dominick walks over to pull the card free, it has moved itself to the upper left portion of the target. (00:29:20)
The Likely Lads: A Special Christmas Edition - S3-E1
Continuity mistake: There is a white Ford Cortina driving between Bob and Terry's cars, but when they stop at the second set of traffic lights the Cortina has disappeared.
A Community of Victims - S3-E3
Continuity mistake: Officer Ripley's shoes change from black to white as he chases the ambulance, then back to black.
Continuity mistake: When Uhura's rescue party is in the transporter, Chapel's uniform is blue. When they materialize on the planet, it's red for a moment, then blue.
Factual error: The armed robbery is reported by the radio call as happening in "4014 Nostrand Avenue", which is a real street in Brooklyn. However, the first detectives to respond to the dispatch identify themselves as being from "Manhattan South" (makes sense, Kojak being a Lieutenant of the fictional 11th Manhattan South precinct), and the rest of the episode is set obviously in Manhattan. That's many miles away.
Revealing mistake: 44/34 Nick Newman is hit from behind and knocked unconscious. However, he bows his head and braces for the blow before he is hit. (00:48:00)