Continuity mistake: When Jefferson hands Emma the scissors, the sharp end is pointing towards Emma. However in the next shot the sharp end is pointing in the opposite direction. (00:24:35)
Revealing mistake: As Moe French steps out of his florist's van, he is greeted by Mr. Gold and his lackey. As. Gold says, "Well, this is just perfect", in the background, you can see the clock tower building, but without the clock tower (the actual clock tower is CGI). (00:03:50)
Continuity mistake: When Emma arrives at the restaurant, as the elevator opens, a waiter walks past. In the next shot, the waiter walks past the elevator again. (00:04:55)
Continuity mistake: When Emma meets up with Ryan at the restaurant, as he says, "Well, it is the Internet", Ryan is positioned next to Emma and moves to walk around her. In the next shot, he is already standing behind her as he pulls out Emma's chair. (00:05:15)
The Return - S1-E19
Continuity mistake: When August drives off on his motorcycle, in the close-up of his foot as he walks, the pavement he steps on has concrete paver blocks. In the next shot, where he sits on the motorcycle, the motorcycle is parked in front of the Storybrooke Pet Shelter, and the pavement has changed to asphalt concrete. In the next shot, the vehicle, seen from a different angle, is parked in front of the business located on the left side of the pet shelter; easily seen from the pavement, which is now paver blocks again. (00:16:45)
Continuity mistake: When Emma is driving through downtown Storybrooke, in some shots, the real-life businesses in Steveston Village (the Canadian town which doubles as the town of Storybrooke on Once Upon a Time) have not yet been transformed into Storybrooke businesses. For example, a sign on a building on the left side of the road (in the first shot) says Pacific Net and Twine, and on the other side of the street (in the shot where Henry is heard saying, "Forty-four, not-telling-you street"), the name on the local bakery, which is Romania Country Bread, and is sitting next to two businesses called Kaido and Splash. In "The Thing You Love Most", the buildings have been transformed into the Storybrooke businesses seen throughout the rest of the series: For example, Pacific Net and Twine has become Atlantic Twine and Net, the bakery has been renamed Storybrooke Country Bread, and Kaido and Splash have become Standard Clocks and Neighbor's, respectively. Also, in "The Heart is a Lonely Hunter", when Graham first meets the wolf, as the wolf walks away from him, in the background, the name "Pacific Twine and Net" appears on a window pane. (00:15:40)
Revealing mistake: As Mr. Gold bangs his head on the table after being spritzed with pepper spray, you can see that one performing this action is Robert Carlyle's stunt double, and that the stuntman merely hits the table with his hands. (00:10:20)
The Thing You Love Most - S1-E2
Continuity mistake: When Emma arrives in Storybrooke in "Pilot", the sign on the clock tower is a green house-shaped structure, and there are six small boarded up windows on The Tower. They are still there when Henry is watching the town clock from his window in the evening at the end of "Pilot", and in the beginning of this episode. However, the following morning, the sign on the clock tower is a white rectangular sign, and white signs are covering the windows. The clock tower remains this way for the rest of the series, with two exceptions: When Regina looks out the window and sees the purple cloud approaching in "A Land Without Magic", and when the Shadow flies through town after being released in "The New Neverland", the green plaque and the windows can be seen on the clock tower. (00:00:40 - 00:01:15)
The Heart is a Lonely Hunter - S1-E7
Continuity mistake: As Emma exits the crypt, in the wide shot, Regina's left hand, holding the flowers for her father's grave, is at her waist. In the next shot, her hand is down by her side, before she brings it up to show the flowers. (00:33:35)
True North - S1-E9
Continuity mistake: As Emma returns to the apartment, Mary Margaret is folding clothes on her bed. As she sees Emma, she's holding out her arms, but in the next shot, her arms are down by her side. (00:37:05)
The Thing You Love Most - S1-E2
Factual error: This episode takes place the day after Emma decides to stay in Storybrooke and time started moving. According to "The Stranger" and "Selfless, Brave and True", August woke up in pain in Phuket on October 24, 2011 at 8:15am, the exact minute that Emma decided to stay in Storybrooke at 8:15pm. Since Thailand is 12 hours ahead of Maine's timezone, this means that time started moving in Storybrooke on October 23, and that this episode takes place on October 24. During Regina's conversation with Emma in her office, she says, "Did I know that my son comes to my office every Thursday at precisely 5pm so I can take him for dinner before his therapy session? Of course I did." However, October 24, 2011 was a Monday. (00:30:05)
Factual error: In "What Happened to Frederick", Kathryn learns about David's affair and confronts Mary Margaret at school (after taking her anger out on Regina), where students and teachers are milling about. Later, she apologizes to Regina for "what happened yesterday", whereas Emma, earlier that day, seeks out Henry at school. Kathryn leaves Storybrooke the same day, and mysteriously disappears. According to Kathryn's phone records in this episode, she disappeared on a Sunday. However, the day she left, and the day before, was a school day. In the U.S., school classes are not in session during weekends. (00:38:25)
Continuity mistake: When Mary Margaret and Emma are walking down the street, as Mary Margaret says, "This is the best I can do", she begins to walk past the corner of a building. In the next shot, they begin to walk past it again. (00:05:15)
What Happened to Frederick - S1-E13
Revealing mistake: At Granny's, when Emma and August ride off on the motorcycle, you can see that the one driving is actually Eion Bailey's stunt double. (00:21:45)
Continuity mistake: In Pinocchio's home, when Jiminy Cricket pops out of the cuckoo clock, a navy officer doll can be seen sitting on a table as Geppetto goes to release the cricket. In the first shot, the doll is perpendicular to the chair next to the table, but when Jiminy says, "It's okay. He meant no harm", the doll has turned around 90° and is parallel to the chair. After the Blue Fairy shows up, the doll is back to its original position. (00:12:30)
Continuity mistake: In "The Shepherd", Kathryn is showing David their house, and you can see that the street number on the Nolans' house is 244. In this episode, when Emma is looking at Kathryn's phone records in the evening, the phone records list her address as number 4. (00:38:25)
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)
Continuity mistake: In the scene where Snow is in Emma's nursery room, trying to convince Charming to talk to Rumplestiltskin, the shots have been flipped. The easiest way to spot this is Charming's scar, which is on the wrong side of his face. (00:10:30)
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.