10 Doctor Who Characters You Didn't Realise Probably Died Horrible Deaths
6. John Smith
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In Human Nature, the Doctor uses a Chameleon Arch to disguise himself as a human, allowing him to live undetected as mild-mannered English school teacher John Smith.
It’s easy to watch the story and simply think of Smith as the Doctor suffering from a temporary amnesia that gets fixed at the end, but that’s not how other characters talk about it at all.
For all intents and purposes John Smith is a completely independent person from the Doctor, and that person has to die to allow the Doctor to return. An innocent man has to commit suicide for the benefit of someone he’s never met, and, from his point of view, may not even exist.
As viewers we know that the Doctor must come back so it's easy to overlook how traumatizing it must've been for John to pull the trigger, and the fact that it happens offscreen makes the weight of his sacrifice even easier to brush aside.
So while not necessarily as physically horrible as other deaths, John Smith’s end might be the most existentially horrifying. Imagine discovering that your entire life is a lie and that your body actually belongs to someone else – someone who is considered so much more important than you that you are left with no option but to kill yourself so that this other person can return.
Once again, THIS IS A FAMILY SHOW.