10 Best "Everything You Know Is A Lie" Moments In Doctor Who
3. John Smith Accepts His Fate (Human Nature/The Family Of Blood)
This entry is a little different, as instead of the audience discovering a lie, it's about a character on the show realising the truth.
That character's name is John Smith - aka The Doctor in disguise.
After the evil Family of Blood begin pursuing the Doctor and Martha, our hero decides to mask his Time Lord energy by pretending to be a human. He transfers his essence into a fob watch, asking his companion to guard it.
The Doctor forgets everything, truly believing he is a humble English schoolteacher. He even falls in love with a regular human woman - although being a Time Lord never put him off that in the past! Cough, Rose.
The penny drops for old Johnny boy once the Family catches up with him. Torn between his beloved Joan and his role as the universe's defender, he tearfully opens the watch and brings back the Doctor.
It's a really sad scene, aided by visions of what his life with Joan could have been. It's challenging, thoughtful stuff, which is what makes this episode of Who so damn great.
We're not crying, you're crying! Okay, we're crying too.