Line of Duty stars Martin Compston and Vicky McClure revealed on The Jonathan Ross show that they have a secret voice they talk to each other in on set.
And the actors admitted their co stars including Adrian Dunbar, who plays Superintendent Ted Hastings, cannot stand the voice.
After much persuasion from host Jonathan, the giggly pair demonstrated the voice they use - much to the amusement of fellow guests Ashley Banjo and Ellie Simmonds.
Jonathan said: "I have read that there is a silly voice you use with each other, and it annoys everyone else after a while but you guys still find it hilarious?" "We are not doing the voice!
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