Revealing mistake: When Sgt. Troy throws the grenade at the Gestapo agents barricaded behind the table, it is thrown wide right, yet the pyrotechnic explosion is dead center of the table barricade.
Revealing mistake: 1967: Barnabas and Vicky are talking in Collinwood's foyer when a great deal of noise starts interrupting the scene from backstage. You can hear coughing, several bumps and crashes, shouts, and finally, a fire extinguisher going off. Meanwhile, the distracted actors are completely blowing all their lines - but the unstoppable taping goes on.
Revealing mistake: When Briggs disguises himself as Rogosh's defense attorney, the glasses he puts on very obviously have no lenses in them. (00:26:05)