Where Have You Gone, Billy Boy? - S7-E18
Character mistake: When Kate's corpse is discovered, her mouth can be seen moving slightly. (00:23:50)
Where Have You Gone, Billy Boy? - S7-E18
Continuity mistake: When Stanton finds the dummy, its jacket is closed across the chest, revealing only a small portion of the yellow T-shirt underneath. The shot briefly cuts to his assistant, and when it returns to the dummy, the jacket is pulled open, leaving the T-shirt fully visible.
Where Have You Gone, Billy Boy? - S7-E18
Continuity mistake: When Stanto discovers the dummy, it is covered with a green sheet, and a blue cloth is draped over its head. After he removes the green sheet, the blue cloth has been replaced by a grey-and-black one covering the dummy's head.
Where Have You Gone, Billy Boy? - S7-E18
Revealing mistake: When Vic De Marco enters the dressing room, an actor's mark - visible as a white spot - stands out on the red rug.
Answer: In a flashback scene, it was shown that he had a violent temper, so it stands to reason that he finally killed her in a fit of rage.