The things we think are true about ourselves go "out the window" in the face of social pressure, according to TV illusionist Derren Brown.
In Channel 4's Pushed To The Edge, he will test the extent of social compliance and obedience to see whether an ordinary man can be persuaded to push someone off a roof.
Brown told the Press Association: "There's this dissonance that springs up between what your values are and what you find yourself doing. So whether or not he pushes the guy off the roof in the end, doesn't say anything about his internal values.
"One of the things I often find when people watch these shows is often people say: 'Oh, it's all fake, it's all set up', because they don't think that they themselves would act in that way in that situation. Because we're all very aware of what our values are, and what we think we'd do.
"But we forget that what overwhelms that - then those values becomes irrelevant at the end. The social situation is much more powerful, ultimately."
In the one-off psychological experiment, Brown selects an unwitting man - Chris Kingston - who had previously applied to be part of a show.
The man is invited to a charity auction, where actors create a rapidly-escalating situation leading to a decision on the venue's rooftop.
Brown said: "What you see in this show is a tension that builds up between that innate sense of good that he has, and the stuff that he's being made to do.
"And it's interesting, because that's where we're terrible at predicting what we would do in those situations... We think that we think in isolation, but the reality is, these are social situations, where those things - the stuff we think is true and solid about ourselves - just very quickly goes out the window."
He explained: "If you took a group of people up on a roof and told them to push somebody off, no one would do it.
"If you want to get somebody to do something totally against their moral character, you have to slowly turn the heat up.
"When they cook frogs, they put them alive in water. But you have to put them in cold water and slowly turn it up. If you just put them in hot water, they leap straight out. And it's the same thing. You're just slowly turning the heat up."
:: Derren Brown: Pushed To The Edge starts on Channel 4 on Tuesday, January 12 at 9pm.