Celebrity Big Brother contestants have been subjected to psychological tests for the very time prior to entering the house.

The show - which hasn't aired for two years since the Jade Goody and Shilpa Shety race row - is back tonight after a long break.

But to avoid any of the drama which took place in 2007, producers have gone through a thorough selection process including psychological tests.

A source tells the Mirror, “The tests probably weren’t good for their egos, but they were important to try to get a good trouble-free series.”

Executive producer Sharon Powers adds, “We made it really, really clear exactly what kind of language and behaviour would not be tolerated.”

The faces going into the house tonight are, Verne Troyer aka Mini Me, ’80s singer Steve Strange, rapper Coolio, A1 popstar Ben Adams, politician Tommy Sheridan and presenter Terry Christian.

Plus, La Toya Jackson, Ulrika Jonsson, Shameless actress Tina Malone, glamour girl Lucy Pinder, Liberty X singer Michelle Heaton and former Sugababe Mutya Buena.