David Tennantis set to play the notorious serial killer Dennis Nilsen in the new ITV show Des, and the first look trailer shows him in the role for the first time. 

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In the trailer, which also stars Daniel Mays and Jason Watkins, the pair can be heard interviewing Dennis, who admits that he has killed "15 or 16" people in his life, adding: "I look in the mirror and I just see my, friendly, helpful, responsible me." The trailer also looks at Brian Masters' (Jason Watkins) fascination with the serial killer, shaking his hand upon meeting him.