The Thing You Love Most - S1-E2
Continuity mistake: When Regina picks up Malificent's staff, Lana Parilla's black feather tattoo is visible on her right wrist. The tattoo can also be glimpsed when Regina bangs a gavel to start the meeting at the Storybrooke Town Hall in "Fruit of the Poisonous Tree." For the rest of the series, the tattoo is missing. For example, when Regina hands Emma a drink in "Pilot", when she tries to burn the book of spells in "We Are Both", and when she tries to make a potion in "Witch Hunt", her wrist is bare, and there is no tattoo. (00:07:25)
The Thing You Love Most - S1-E2
Continuity mistake: When Regina is talking to Sidney by the apple tree, as Sidney says "Bounced around all over", Regina is picking an apple. In the next shot, she's already holding it in her hands. (00:11:10)
The Thing You Love Most - S1-E2
Continuity mistake: When Emma walks Henry to school, as they exit Granny's, the clock tower building is behind them, and they are walking away from it. But when Henry says "They don't know. It's a haze to them", the clock tower building can be seen on the other side of the street, and they are walking next to it. (00:12:35 - 00:13:10)
The Thing You Love Most - S1-E2
Continuity mistake: Throughout the scene where Emma walks Henry to school, the surroundings change between shots. For example, when Emma asks, "Because I'm the daughter of Snow White and Prince Charming?", they are in front of a clock store. In the next shot of Emma, there's a completely different shop behind her, even though neither of them move. (00:12:35)
The Thing You Love Most - S1-E2
Continuity mistake: When Emma is walking Henry to school, there are several instances where they walk past the same building more than once. For instance, as Henry says "Luckily, I have a plan", they pass a shop with a wooden rudder on display in the window. When he says "Don't let her see these pages", they walk past the same shop again. (00:12:40 - 00:14:00)
The Thing You Love Most - S1-E2
Continuity mistake: When Emma is wearing the red dress in "Pilot", she has a mole on her chest. In this episode, which takes place two days later, when she's in her white tank top, the mole is gone; this is best seen when Graham is taking mug shots of Emma, and she says "He's terrified of her, like everyone else in this town." This is probably due to the fact that in real life, Jennifer Morrison has had several moles removed from her body. However, there was no time for Emma to do the same, and even if there were, she'd have a fresh scar or stitches. (00:20:30)
The Thing You Love Most - S1-E2
Continuity mistake: In the beginning of the episode, as Regina stops below the clock tower and gazes at the clock, there is no sign on the blue building in the background, next to Storybrooke Country Bread. When she notices Emma's car, there is a sign on the building. (02:55:00)
Snow Falls - S1-E3
Continuity mistake: As the trolls search through Prince Charming's belongings, one of them is seen pulling out Snow White's wanted poster from the bag, but in the previous overhead shots, he was already holding it in his hands. (00:27:45)
Continuity mistake: As Ashley tries to break into Mr. Gold's safe, which is hidden behind a painting, in the first shot, she's moving the painting with her left hand. In the next shot, her right hand is up by the painting, and the lever on the safe has changed position, even though there was no time to turn it. (00:09:55)
Continuity mistake: When Graham offers Emma the job as a deputy sheriff, when he gives her his card, you can see two women a few meters behind Emma, walking on the pavement, toward the camera. In the next shot of Emma, only a few seconds later, the women are still walking in the same direction, but they are much further away from her than in the previous shot. (00:16:15)
Continuity mistake: The feathers in the enchanted quill that Cinderella gives Rumplestiltskin keep going from being smooth and even to being frayed between shots. (00:28:55)
Continuity mistake: When Ashley is holding baby Alexandra while Emma comes in, her left hand repeatedly changes position between shots; for example, when Emma says "It's pretty", her hand is on one side of the baby's head; in the next shot, it is on the other side. (00:36:25)
Continuity mistake: After Henry runs up the stairs, he puts his backpack on the bed, with the backside facing upwards. When he takes off his shoe and throws it on the floor, the top of the backpack is facing upwards. When Regina enters his bedroom, the backside is facing up again. (00:38:35)
Continuity mistake: When Henry lies on the bed, the position of his legs goes from one leg being crossed over the other, to being parallel to each other, between shots. (00:38:40)
Continuity mistake: When Sean is visiting Ashley at the hospital, as he says "Yeah, I'm back", baby Alexandra is waving her tiny hands in the air. In the previous and following shots, her hands are down. (00:39:10)
That Still Small Voice - S1-E5
Continuity mistake: During Henry's first therapy session, as Archie says "So all the crickets in Storybrooke, they were once people too?", Archie's holding a coffee cup in his hand. In the next shot, the cup is sitting on the table. (00:02:45)
That Still Small Voice - S1-E5
Continuity mistake: After Regina tells Emma to clear the crowd away after Henry is rescued from the collapsed mine, Regina's hand goes from being on Henry's face to his side/waist between shots. (00:34:35)
The Shepherd - S1-E6
Continuity mistake: When the twin brother is getting ready to slay the dragon, you can see the scar on his face which hasn't happened yet. In scenes before and after, the scar is not visible. (00:24:00)
The Shepherd - S1-E6
Continuity mistake: When Mary Margaret is sitting at the bar with Doctor Whale, the straw and lemon slice in the empty drink in front of her keep changing position between shots. (00:39:40)
The Heart is a Lonely Hunter - S1-E7
Continuity mistake: When Graham is arguing with Emma at the beginning of the episode, in the very first shot outside Granny's, they are approaching a shop called Worthington's Haberdashery. As the shot ends, they are still a few meters away from it, but in the next shot, they are already in front of it. (00:01:50)
Answer: He knows who she is because he knows that the fairy tales are true. He was also shown to sneak out to go see Emma or someone else. Sometimes he succeeded, sometimes he didn't. This is how he knew to look for her despite his strict mother.