the dailymash

Following William's use of an RAF helicopter to arouse his girlfriend earlier this year, he now wants to 'step things up' by deploying the world's most feared commando unit.

A friend of the couple said: "The first scenario will involve Kate being 'kidnapped' by 'Iranians' and held in a secret location, though they will probably just use the big dirty sex room at Clarence House.

"William will be dressed all in back, with camouflage make-up and one of those little knitted hats. Very butch, very hunky.

"Meanwhile they've hired a couple of Spaniards to play the terrorists, while Kate will be taken from her bed in the middle of the night wearing nothing but a flimsy nightie.

"After being held for the best part of 20 minutes, all hell will break lose when the SAS crash through the windows, chuck a couple of smoke bombs and shoot the Spaniards.

"Then William will swing in and hopefully land on the bed. Then they'll do it."

Other scenarios include Miss Middleton being tied up and held in a castle and being tied up and held on a yacht.

The friend added: "It is vital that he familiarise himself with the work of the armed forces, so the final game will see William being tied up while Kate rescues him wearing nothing but Doc Martins and a balaclava."