Revealing mistake: At the beginning of the episode when Emma is talking with Norman, she drops the newspaper (of Bradley) in front of him. If you pause it and read the newspaper you can see the text has been repeated once for the text about Bradley and many more times for the news item below that. (00:41:35)
Revealing mistake: In the scene where Norman visits Caleb at the motel on his own, after hearing Norma and Dylan argue, he gets into an argument with Caleb. Norman then pulls a knife out high above his head, at which point you see it is a prop/rubber type knife. The handle aimed at Caleb but the force Freddie Highmore has used to pull the knife up and back causes the blade to bend and aim toward the ceiling.
Revealing mistake: Norma is driving her car as landscape and cars traveling opposite her flash by. In her driver side mirror, there is no reflection of the cars passing by, the road, or any landscape. The mirror is blank.
Revealing mistake: The open eyeballs of Norma Bates' corpse move as Norman holds her head in his hands.
Revealing mistake: When Caleb visits Emma and Dylan, Caleb holds baby Kate. When he gives her back to Dylan, the baby is a doll.