Continuity mistake: Although Clara kicks her shoe at the Mouse King's head, when she gets down from the mantelpiece, it is back on her foot with no sign of her having retrieved it.
Continuity mistake: When Emily falls off the roof, one shot shows her falling with her back first and her legs together. Then the shot changes to her mom, and back to her, at which point her legs are further apart, she is angled more headfirst, and is still at the same height.
Continuity mistake: After Marnie tells Dylan his password, she gives the headphone to her grandmother to chase after Luke. When she reaches Luke, Marnie has the headphone to talk to Dylan while her grandmother is still in the same spot that she was in.
Continuity mistake: When Sam is amazed by the power of time travel, the trees behind him change between shots. (00:03:59)
Continuity mistake: In the shot of everyone chanting, "disco ball!" Hermey is seen in the background, but two shots later, Hermey has disappeared. (00:19:00)
Continuity mistake: The arc-shaped garden plant directed the protagonist to someone who can help him. A nasty human armed with shears walks by and starts his torture; he kneels by the plant, in a zone with no shadows, and in the next shot the whole section of ground is in the shade. (00:39:40)