Piers Morgan has revealed that he had to reassure Dame Joan Collins that Line of Duty actor Martin Compston did not want to kill her, after he was seen performing a throat-cutting sign with his hand at the National Television Awards.The TV personality quickly set the record straight, telling the legendary actress that it had everything to do with football and nothing to do with her.When Joan Collins arrived on stage at the NTAs, she received a standing ovation from the audience as Simply the Best played out in the auditorium.However, eagle-eyed viewers of the televised ceremony spotted the 37-year-old actor, who was sitting down in the front row, performing the sinister sign.He was in fact reacting to the song that was being played as she.