The foursome pose in front of blinding spotlights along with hosts Ant & Dec and Britain's Got More Talent presenter Stephen Mulhern for the seventh edition of the ITV show.
a trailer for the new Britain's Got Talent, in which the judges and hosts show off their hidden skills.
The clip ends with Walliams being strapped to a spinning wheel as Cowell whips him.
Britain's Got Talent will return to ITV this Saturday (April 13) at 7pm, clashing with BBC One rival The Voice UK for 80 minutes.
Speaking to Digital Spy last week, a BBC insider said the corporation was 'disappointed' to see BGT moved closer to The Voice's 6.45pm time slot.
However, Dixon has described the clash as "a positive thing", saying: "At the end of the day both shows benefit because everyone's talking about it."
The contestants featured in the opening episode of this year's Britain's Got Talent have also been revealed today.