Revealing mistake: When the camera follows a man through a curtain to reveal the Eavesdown Docks on Persephone, an extra in a white shirt, black vest and straw hat can be seen standing still on the left looking straight into the camera. He then looks away and starts walking. He was waiting for his cue from the director. Several seconds later, the same extra is seen again behind Mal and Kaylee walking in the opposite direction he was just going, giving the impression that the scene wasn't filmed on a location but in fact a small set and they could only afford so many extras.
Deliberate mistake: After the Crazy Ivan, where they escape from the Reaver ship, the shot of Mal, Wash and Zoe celebrating on the bridge. Wash has his hands out in front of him like he's still holding the stick, but there's nothing in his hands. In the commentary, Joss Whedon mentions that, in order to get the shot right, they had to move the seat back far enough that Alan Tudyk couldn't reach the controls, so they instructed him to mime it.
Continuity mistake: Just prior to the crazy Ivan, Kaylee tells Jayne to cut the hydraulics to the port engine, yet it is the port engine which rotates to perform the maneuver. Also, the cut scenes of the engine thrusting just prior to and after the crazy Ivan are reversed.
Continuity mistake: The first shot we see of Nandi waking up shows her hair loose on the pillow, and her hand curled up on the sheet beside her; in the next shot, a close-up, her hair is mostly tucked behind her ear and her hand is closer to her face than previously. (00:25:10)
Continuity mistake: When Nandi is killed, she falls to the floor on her back, her left arm by her side and her right on the floor by her head. We see her in this position a number of times, but when Mal and Inara look at one another at the end of this scene, Nandi's left arm is now lying across her chest. Neither of the other characters did this to her. (00:35:00)
Revealing mistake: When Nandi confronts Rance stealing the baby, it is a plastic doll and not a live child in his arms. (00:35:40)
Continuity mistake: When Mal and Nandi are talking and drinking on the couch, the position of Mal's left arm keeps changing between shots. In both the closeup shots of Mal and Nandi, his arm is resting next to her on the couch, but in the shot of them both, his arm is behind her.
Continuity mistake: In the scene where Jayne is telling Simon and River to keep clear of Saffron, he is holding some things wrapped in tin foil (possibly food). He places them on a table next to him. River then calls Saffron a liar. In the following shot of Jayne, one of the food packets has been torn open. River later says that "Jayne" is a girl's name. The food packet that was torn open is now intact.
Continuity mistake: When the crew are planning how to break into the Bellerophon Estates, Mal and Saffron use Serenity's port (left) shuttle to get to the island. But when Wash flies Serenity underneath the disposal bin, the shuttle is back even though Mal and Saffron have yet to return. We never see or hear of the shuttles being able to return to Serenity by themselves and it wasn't part of the agreed plan.
Continuity mistake: When talking to Saffron after being caught by her husband while holding the Lassiter, Mal refers to her as 'Yo/Saff/Bridge', an amalgam of her three aliases, Yolanda, Saffron, and Bridget. The subtitle reads this as "Speaking Chinese."
Continuity mistake: After Durran calls the police and Mal and Saffron try to escape, they leave the Bellerophon Estates through a door which uses a crash bar to exit. However, when the guards arrive at the door, it has changed colour and has suddenly started using a regular handle.
Revealing mistake: When Simon prepares an injection for Jayne, you can see him insert it and draw back a considerable amount of fluid from the medicine vial, but the level of liquid in the vial does not drop.
Continuity mistake: At the end, when Inara is closing the lid on the trash container there are three shots. From behind Inara, she has her gun in her lap (in her right hand) and is waving with her left, but from Saffron's point of view Inara has both hands in her lap, then Inara is back to waving again.
The Message - S1-E15
Other mistake: The characters in this show often use the made-up curse words 'gorramn' and 'gorrammit.' Toward the end of this episode, just as Tracey grabs Kaylee as a hostage, he shouts, "Gorrammit, Mal." The subtitles read: "You're a rabbit, Mal." (00:35:50)
The Message - S1-E15
Visible crew/equipment: Tracey threatens the crew with a gun on the bridge when he hears that they're about to call the cops. He says that he'll blow a hole right through Wash if they do. There is a shot of Mal saying "You mailed your ugly business to Zoë and me, Tracey." As he says this, a crew member's hand can be seen above them (through Serenity's windshield on the left of the screen) grabbing one of the pieces of fallen ice.
The Message - S1-E15
Continuity mistake: At the beginning of the episode, when Jayne reads in the note from his mother that she enclosed something in the box for him, there is a shot of Zoë reaching for a crowbar to open Tracey's coffin. Jayne's left hand is visible on the far right of this shot, holding the hat that his mother knitted for him. In the following shot he takes the hat out of the box despite already having it in his left hand in the previous shot.
Chosen answer: One of the premises of the show is that the two major Earth societies that survived, and ultimately merged, were the Chinese and Americans. As a result the common language includes much Chinese. Clothing, signage, and building designs also have a heavy Chinese influence.