Visible crew/equipment: During the scene when Phoebe breaks into the other Phoebe's house and gets caught, the older Phoebe was telling the younger one that the man in the photo is not Frank Buffay, but is Chuck Mangioni. Right after that, as Phoebe 2 walks towards the camera, you can see that the door behind her moves open, and there is a visible shadow of someone who walks by that doorway. (00:19:00)
Other mistake: When Phoebe breaks into the other Phoebe's house, after she mentions that the man on the picture is "Chuck Mangionne" the door behind her opens by itself. (00:19:40)
Continuity mistake: At the end of this episode, Ross opens the door of Rachel's room, says "Hi", and then closes it. However, in the next episode (The One With The Jellyfish), this scene is shown again and changed: Ross opens the door of Rachel's room, says "Hi", and doesn't close it - he talks with Rachel and Bonnie with the door open. (00:21:05)
Visible crew/equipment: When Bonnie first arrives at the beach house, when she enters the door look at the top of the screen above the left door and you will see a microphone dip into the shot for a second before the camera changes. (00:10:55)
Continuity mistake: Near the end, when Joey is asking Ross if Bonnie's room will be free tonight, he is pointing his hands at Ross. In the very next shot they are in his pockets. (00:20:50)
Continuity mistake: When Phoebe goes to the other Phoebe's house, it's raining, but when Phoebe gets into the house her hair and her clothes are dry. (00:05:00)
Continuity mistake: When the six friends arrive at the beach house notice the sand between shots. At first it's all wet due to "flood damage", two seconds later the sand's dry. (00:05:30)
Factual error: When the gang all see the beach house for the first time, it's covered in a layer of sand, which is supposedly left over from a recent flood. Well, if there really had been a flood, there would have been mold on the walls and debris or junk from the outside, and the sand wouldn't have been nice and clean and dry; it would have been moldy. And there would've been a pattern, likely on the walls, of where the water rose up to and where it receded. Not only that, but how did it get in? All of the doors and windows are intact. (00:04:40)
Continuity mistake: When Phoebe goes to visit her mom for the first time, she takes a cookie from the cookie jar and leaves the lid off. But in one shot, the lid is back on. The lid is back off in the following shots. (00:06:36)
Continuity mistake: When Rachel tells Ross that she is still in love with him, her hair keeps changing from behind her ear to down when the camera changes angles.
Continuity mistake: When Joey wakes up all covered in sand, his right "breast" has a big crack. But when the camera angle changes, the crack has gone.
Suggested correction: The crack comes and goes as he breathes.
Factual error: When Bonnie shaves her head, Rachel is supposed to have given her the razors (according to Bonnie.) Nope - the kind of razors needed to do that kind of close shave are a very particular kind, and Rachel isn't going to have them unless she also shaves her own head. It also wouldn't make any sense for Bonnie to have used her own razors; she's not going to carry them around with her unless she's planning to use them.
Suggested correction: Considering Bonnie always used to shave her head, it's not beyond the bounds of possibility that she just kept a razor on her in case she wanted to do it again. She's an impulsive type of person, after all.
