Revealing mistake: In the scene where Bond is trapped in Largo's shark-infested pool, he uses his mini air tank to breathe. In most of the subsequent shots, look closely at the actor's face - it looks a lot more like a stuntman than Sean Connery. (01:20:20)
Revealing mistake: After Manco beats up Cavanaugh and places Cavanaugh's back up against the bar, while Manco faces him, three of Cavanaugh's henchmen appear at the entrance of the bar demanding that Cavanaugh be released. Manco turns around and kills all of them with his pistol, while Cavanaugh falls to the floor crawling toward his gun. Manco is walking toward the entrance of the saloon with his back to Cavanaugh. Manco draws his gun and kills Cavanaugh without looking at him. If you look closely at the tip end of the pistol, you can see that the only thing that Manco would have killed was the saloon floor. (00:17:00)
Revealing mistake: The suit of armor is knocked down by a hand, but when we see it fall there's a string pulling it for a more spectacular fall. (01:04:35)