Continuity mistake: When Marcus and Joan are watching Gephardt's video, he says he's taken lives. At this point the play bar is by his fingers. It cuts to Marcus and Joan, and we hear the video continue to play for more than 12 seconds. When it cuts back to the video, the play bar is nearly in the same position, when it should be well past his hands and near his elbow.
Continuity mistake: When Shinwell and Sherlock are playing chess, the captured pieces move around in various shots. For example, Shinwell takes Sherlock's knight, he places it closer to him than the pawn. In the next shot the pawn is closer to him. It changes a few more times as do the captured white pieces.
Continuity mistake: The note Watson picks up changes when it switches to a close up view of the writing. For example, you can see one line ends with "you when" and another line ends with "not" (being underlined). In the close up the corresponding lines end with "you when I" and "not to" (not still being underlined).
Continuity mistake: When Joan is sitting on the couch folding ties while Shinwell tries on a shirt, she has a folded up blue tie with white dots. When the camera cuts back to her and she's now folding a gray tie, you can see the blue tie with white dots, unfolded, lying on the clothes. Previously there was no tie there. And in the next shot of her, she once again folding the blue tie and the gray tie can't be seen.
Continuity mistake: When Joan accuses Agent Whitlock of gathering intel to rip off/ambush/rob the gangs, a woman enters the hall behind her. Moments later, the woman disappears having never walked past Joan or Agent Whitlock. She didn't open any of the doors in the hallway either since she was walking straight down the hallway.
Continuity mistake: While talking Paige picks up a small white Chinese food takeout container to close it and puts it back down on the desk. She picks up a the larger container that has the red pictures and the word enjoy on it and starts to close it. In the closeup she has the small white container back in her hand.