Revealing mistake: When Pope bursts into the infirmary and sees Westmoreland's body, watch the collar of Westmoreland's jacket. You can see it moving up and down as though he's breathing. (00:03:30)
Revealing mistake: After Pope enters Scofield's cell to see the escape hole, we see him standing outside the cell looking out at everyone throwing toilet tissue etc. If you watch closely right after we see a guy pulling his pillows toward him to tear up, it cuts to another inmate who is throwing stuff out as well. Only thing is, we see the cell door slides to the side slightly which would indicate that the cell doors where not locked. In the event of an escape, lockdown would happen immediately, with all cell doors locked with the prisoners inside their cells. (00:04:00)
Factual error: When they have escaped, and the dogs are barking at them as they hide in the bushes, this couldn't have happened the way the show presented it. The spot that they escaped is on the main road (Collins Street, also, it was to the left of the screen from where Joliet Jake came out in 'The Blue's Brothers) The dogs are barking at them as they hide in the bushes, and that location is on the -other- side of the Prison. There is NO way that they would be able to circle around the prison and get from one side to the other considering in the front, there are fences surrounding the main building, obstructing you from going that way. The back side of the Prison (There it a road next to a junk yard located right next to the Prison, the same road that is used to get to the 'Gate' the cons are looking at when the dogs are barking. That road would have been full of cops, since all the cops are in the parking lot. It would have been more believable if they would have went across the street to where the women's facility was, and were shown on camera looking across to the parking lot out front. (00:05:50)
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Continuity mistake: The blood mark the young inmate leaves on the concrete changes from the time its made until when its found. When its made it is just a small blotch. When Bellick finds it, it is a full on hand print. (00:10:30 - 00:14:25)
Answer: Don Self actually worked with Whistler before he died. And Whistler with the bird book actually knew where Scylla was.