Forbidden Chambers is a time based challenge that first appeared in Series 2, but was only featured once. It returned in series 3 (like all of the other series 2 challenges) and was featured more frequently. Edit
Layout: This challenge has one of the most unique set designs in the original series. Instead, of being one room, the forbidden chamber is made up of 4 separate areas which are all colour coded (green,orange,purple and yellow). Each chamber looks metallic in appearance and has a number of warning signs painted in black. Connecting each of the rooms is an automated metal door which can be used to access the different parts of the floor. It is impossible to see the whole room unless seen above, unlike nearly every other challenge in the series.
Challenge Character: The Jub Jubs are unseen characters and are the focus of this challenge. They are all inside the coloured crates that need to be taken to the respective rooms. It is also shown they are very aggressive, as Wiley Sneak is struggling to keep the lid on its crate in the challenge demonstration as well as being supposedly smelly.
Gameplay: The unfortunates need to ensure that at least two towers of crates are stacked at the end of the challenge (Only the colour of the room and there are five of them). The only way to reach other rooms is to enter rooms when they are not occupied. To do this, the unfortunates need to bang on the door to activate the mechanism to enter the chamber. In addition, only one colour can be carried at a time. The voice, instructs the saboteur on what needs to be said to the team and how they can lie convincingly (such as what room they are in and what colours they have) she also tells them how the other two unfortunates are doing and their whereabouts (since none of the unfortunates are together and cannot see what they are up to)