Sacha

Revealing mistake: When Clara's dress rips off and is about to fall off the train, Doc saves her. One can notice it's not Christopher Lloyd but his stunt double. (01:41:17)

Sacha ★

Revealing mistake: When Buford is about to duel Marty, the back shots of Doc show his hair short, as opposed to the front shots, revealing it's a stand-in.

Sacha ★

Revealing mistake: When the train pushes the DeLorean and hits 70 mph Doc tries to grab Clara. In the wide shots (where we can't see his face) his coat whips, but in the close-ups where we do see his face the coat flutters, revealing that the train was going much faster with the stuntman.

Sacha ★

Revealing mistake: At the festival, after Marty is given the gun he encounters Seamus and Maggie. Due to the Vistaglide camera effect where Marty was later added to the scene, she is unable to look at where Marty is supposed to be. This is very noticeable when Seamus says "buffoon" and Marty turns around and starts to walk, but Maggie keeps staring at where he was. Also when the scene ends and she looks at Marty and warns him to watch for the future, she's totally missing the spot.

Sacha ★

Revealing mistake: When Marty pours the wake-up juice through the funnel into Doc's mouth, in the close-up the funnel is straight, but we can't see Doc. From a different angle where we do see the funnel stuck in his mouth, check the right side of the screen: The funnel is actually skewed (and seemingly it must have a tap) and the liquid is falling out in large amounts to prevent the actor from drinking it. (01:20:04)

Sacha ★

Revealing mistake: When Clara horseback rides towards the train, when she reaches for the handlebar she is replaced by a very obvious stuntwoman who looks nothing like her.

Sacha ★