Continuity mistake: At the beginning, the way Holmes holds the photo is different in consecutive shots. (00:01:00)
The Rat Race - S1-E4
Continuity mistake: Watson has just been ambushed with a date by her friend at the very beginning. She is reaching for her coffee cup. In the immediate next shot, her hand is down by her side. (00:03:15)
The Rat Race - S1-E4
Continuity mistake: In the final scene Watson finishes tying her shoelaces. Next shot she is still tying them. (00:41:40)
Continuity mistake: In the prison, Captain Gregson takes five shoes out of a suitcase, but when it comes time to leave, Gregson doesn't put the shoes back in the suitcase because they are already there, and he could not have done it without us seeing it.
Continuity mistake: In the beginning, Joan and Sherlock are chatting in the living room. Joan has her hands in her lap, then she is resting her right arm on the arm of the chair.
Continuity mistake: The brownstone has two front doors, an outer door and an inner door. In scenes before this one and after this one, the outer door is made of wood and the inner door has a large glass panel, at the top, but in this episode the outer door has a large glass panel, at the top, so they can see who it is before opening the door.
Continuity mistake: Just before Sherlock and Detective Bell enter the dead professor's office, both are putting on gloves. Sherlock puts on the left first and has partially put on the right. As they enter the office, Sherlock still hasn't put the right glove on at all - he's just starting to do so. (00:05:30)
Continuity mistake: While playing the piano in Justin Guthrie's apartment, he is bare handed. In the next scene when he gets up to point at the blood, he is wearing gloves. (00:24:12 - 00:24:42)
Continuity mistake: Early in the show, when Sherlock is making eggs, he adds milk and sets the jug down. The camera shifts to Watson and back to Holmes, which shows the jug missing. Watson then walks around Holmes and sets the jug down in the spot it was in previously.
Continuity mistake: When Joan meets with her therapist, the nook behind Joan is brightly lit. The nook goes back and forth from brightly lit to very dark, sometimes in the space of a three-second cut to the therapist.
Continuity mistake: Sherlock and Watson are riding in a limousine. They are seated on the back-facing seats of the limo. Thee are 2 passengers seating on the back seats. The street background visible through the back and side windows shows traffic and the limo moving forward. Some shots of Sherlock show the background traffic moving in the right direction (backwards) and one shot shows traffic moving in the opposite direction, as if Sherlock was seating on the back seat or the limo was moving In reverse.
Continuity mistake: While Joan and Sherlock are chatting, Joan is trying to make peanut butter and jelly sandwiches, but the shots alternate between the two and Joan repeats her movements, wipes the peanut butter over and over on the bread, and changes her mind with the jelly bread.
Continuity mistake: When Sherlock first accuses Irene of working for Moriarty, he pins her to a bookcase. When she shoves him away and breaks free, her hair ends up arranged with some strands in front of her. During the following minute, those strands repeatedly switch back and forth from behind her shoulders to in front of them. (00:38:25)
Continuity mistake: When Detective Bell receives a phone call from Gregson in Holmes' house, he rushes upstairs and bangs on the bathroom door - Sherlock is inside, he said he wanted a shower. Bell rattles the handle, but finds the door locked, so he kicks the door in. But Sherlock didn't lock the door. The lock is above the handle and Sherlock did not use it.
Chosen answer: M broke into the brownstone and left a note. Holmes deduced he was staying at a high-class hotel from the soap scent on the note, and gave a picture from a hidden camera to his "irregulars" on the street to stake out hotels. One of them saw him, so Holmes followed him to his next intended victim and knocked him unconscious with a baton.
Sierra1 ★