I was not surprised that the place it occurs was in one of those London town houses with the sunrise symbolic window above it and was the number 33 shockingly (sarcasm).
The episode was supposed to show the power of negative suggestion, "Don't do this!" would mean you do it, which is a theme I've seen alot of in some of the blogs. To show this, he goes to a black/red/white resonating school and uses this synchromystical cube (jack-in-the-box shooting out pillars, see below) And also identical twins talking about an "invisible hand" that opened the box, not them (because they were told not to so are making oddly symbolic excuses).
Also to illustrate the power of negative suggestion, he goes to a circus (below) and tries it on a trapeze artist skipper person. What interested me was when they were doing one of those flashes breaking up the episode they quickly encircled a red square on an air-bag which the trapeze artist landed on. The way the square was blurred as the camera went round and round the freemasonic red square, it seemed quite hypnotic to me (short sequence pictured below).
Anyway, for Lauren's "treat" Derren makes her symbolically electrocute a kitten inside of a cuboid by using negative suggestion "Don't push the button!". He constantly clicks his red and black pen to implant the command of pressing the red button before the time runs out. To help this, as anyone who knows anything about mind control knows, regression to a child-like alter is usually how its done by a trigger word and whatnot, one of the alters created at that young age. Derren asks her to bring some child toys to bring her back to this "more susceptible time". Anyway, she pushes the button with 1 second to go and this is the scene....(second image down) but apparently the cat doesn't die because it wasn't wired up to the mains... She wins £500 and we get some random pictures of her going surfing, yay for Lauren! :S Watch the entire episode at end.