Continuity mistake: A large blue vase in Galba's study keeps moving itself into different positions on the table. Several shots later, it's gone altogether. (00:20:00)
Visible crew/equipment: When Alba says "He's in this room" books start flying off the shelves. You can see the device used to push the books off the shelves come forward then be retracted. (00:41:00)
Visible crew/equipment: At the very beginning of the episode, Nero's ghost appears and raises a knife to attack the heroes, the wires used to move the knife across the room are visible most of the time.
Revealing mistake: Tony and Doug escape the torture chamber through a stone door that looks as thin as a piece of wood and freely moves when they use it to exit the chamber.
Continuity mistake: After the city of Jericho shows up on the screen, Dr. MacGregor is next to and above Dr. Swain, but the next cut shows her closer to Swain.
Continuity mistake: When Rahab approaches three soldiers, the second soldier places his hand on the arm of the first, but when the shot changes, it is now the third soldier with his hand on the second.
Revealing mistake: When the torturer throws himself against Tony, the stone wall buckles when he slams against it.
Factual error: One of the Spanish soldiers lights a torch with what appears to be a hand-held lighter. Early lighters were converted flintlock pistols (not yet invented during the time of this episode) and the earliest hand-held lighter would not be invented until three hundred years after this episode's timeline.
Revealing mistake: After the first Native American is shot in the back with the crossbow, the base used to stabilize the arrow in the back of the actor is visible underneath his clothing.
Revealing mistake: When Doug drops the torch on the gunpowder trail, the ignition of the powder is about one foot before the point where the torch is dropped.
Continuity mistake: In the opening scene of Doug and Tony's landing, Doug lands in a bush, but the next shot of the two recovering has Doug outside the bush.
Continuity mistake: After Doug drops the torch on the gunpowder trail, one of Cortez's men grabs and moves the powder keg out of the way twice.
Revealing mistake: The heavy stone table the mask is sitting on in the cave during the fight scene wobbles when bumped by the cast members.
Revealing mistake: The crossbow a Spaniard uses to shoot the elderly Indian is not loaded with an arrow.
Factual error: Doug and Tony time travel to one million years B.C., where they encounter dinosaurs. Not likely. All the dinosaurs were rendered extinct several million years earlier by an asteroid strike. There weren't any left by 1-million BC. (00:29:45)
Continuity mistake: After falling into the quicksand, Nimon's head and right hand are exposed, but the next shot when Tony and Doug arrive to help, only his head is seen.
Continuity mistake: During Tony and Doug's meeting with Nimon and the Magister, the assistant points his laser gun close to Doug's back, but when the Magister signals to shoot, the assistant is now several paces behind Doug, and there was no time for the assistant to step back.
Continuity mistake: Vokar's assistant brings Tony and Doug into the control room, stopping in front of a dome. The assistant is directly in line with Doug and next to the dome, but the next shot shows the assistant standing further from the dome and towards Doug's left.
Continuity mistake: When Vokar's assistant summons Tony and Doug, they are in a room with very dark walls, but the profile shot of the assistant shows a beige wall behind him.
Factual error: Raul Nimon uses a silencer-equipped revolver during his attack in the tunnel control room. In reality, a silencer on a revolver is useless, as the exploding gases from the bullet discharge (the gun blast) would exit from the space between the cylinder and gun barrel.
