A mother and father who murdered their daughter because she would not embrace their Pakistani culture were given away by a single nod.
A body language expert has analysed footage of Iftikhar and Farzana Ahmed lying to the public about 17-year-old Shafilea's 2003 disappearance, claiming they were being racially victimised, for a documentary.
However, according to expert Cliff Lansley - who shares his findings on Investigation Discovery's Faking It: Tears Of A Crime - he gives a self-incriminating nod as he gives his response.
Mr Lansley explained that the fact that his head moved in an up-and-down motion at the moment when he was pressed on his involvement in the murder, at almost the exact time he expresses his verbal denial, is a significant indication of guilt.
Nine years after Shafilea disappeared, the truth finally came out in court - her father had stuffed a plastic bag in Shafilea's mouth, holding it there until she stopped breathing.
Tragic
Also very interesting how this expert analysed the interview.