The Night of the Brain - S2-E21
Revealing mistake: Mr. Braine screams as his steam-powered chair crashes into the bandstand. If you look closely at the next shot, just before the explosion, you can see that the dummy now in the chair has its head bowed forward. It also has light brown hair, rather than Mr. Braine's silver hair. (00:47:10)
The Night of the Brain - S2-E21
Revealing mistake: When Gordon is looking outside on their train car platform, it is obvious the background desert scrub is a painted scenery flat.
The Night of the Brain - S2-E21
Revealing mistake: Mr. Braine fires a mini-rocket at Brendage, killing him. But a poor camera angle reveals the explosive charge going off in the wall more than two feet to Brendage's left. From the angle at which it was fired, the rocket couldn't possibly have hit him. (00:21:45)