Character mistake: In an early scene with Yvonne Hartman, she says "We've just measured the ghosts' energy at 5000 gigawatts." There are at least two mistakes here: (1) watts are a unit of power, not of energy (that would be joules); (2) later on, when Hartman is showing the Magnaclamp to the Doctor, she refers to imperial tons and says "Torchwood refuses to go metric", but a gigawatt is a metric unit.
Character mistake: When the Doctor is taking Donna to 4.6 billion BC to watch the formation of the Earth, he says that it is the furthest back the TARDIS has ever been. But in the 5th Doctor episode "Castrovalva", the TARDIS drifted to 13.2 billion BC and the formation of the galaxy.
Character mistake: Idris (the human form of the TARDIS) berates the Doctor because the doors of the TARDIS open inwards, pointing to the notice on the left hand door which says 'pull to open'. Whilst it is true that police boxes did open outwards, the notice is actually referring to the telephone in the small recess behind the notice. The public are instructed to 'pull to open' the small door to access the phone. Consequently, the small door does open correctly, as in the notice.
Add timeJeff Walker