Children of Earth: Day One - S3-E1
Revealing mistake: When the children are possessed by the 456, they're supposed to be frozen and stare blankly ahead. But during the second possession, as the camera is panning across a school playground, a boy on the far right is looking directly at it. As it moves closer to him, he swivels his eyes back to where they're supposed to be. (00:16:30)
Chosen answer: As long as Jack's been in charge of it, Torchwood Cardiff has had a different agenda than Torchwood One. Tosh and Owen were there to watch for signs of the 10th Doctor, however, it was the 9th that showed up when the ship crashed in London.
Captain Defenestrator