Since 2000 BB has graced Channel 4, not just in the standard form, there's been Celebrity Big Brother and Big Brother: Celebrity Hijack. Could it be that there really is nothing else left to try and the original format is out-dated?

Film and television studies lecturer Dr Belinda Smaill: "I think the novelty of the social experiment has worn off. People want to see extreme situations or they want to see people change and overcome something or be tested in an immediate way. Big Brother, as one of the very early reality shows, it's very straight forward and there's little you can do."