Revealing mistake: After Mr. Heckles has been taken away, in the last wideshot while everyone's still standing in the hallway, when this is viewed on the DVD (Warner Bros. S2 set) we can see a long black line on the floor (as noted in another mistake). The problem is that when this is viewed online on Netflix, even though we can see the very same area of floor, that black line has been blurred out. Weird that it wasn't edited on the DVD, and yet it was for the version available on Netflix.
Add timeSuper Grover
Revealing mistake: At the end, when Rachel and Ross are talking on Monica and Rachel's balcony, the edge of the "brick" wall behind them has a gap in it. The facade is obviously a thin plastic sheet that is made to look like bricks and mortar, and it has pulled away somewhat from the surface it is attached to.