10 Greatest "I'm Dead And I Know It" Moments From Modern Doctor Who

10. The Doctor - The End Of Time

There are several options to choose from, both from the Tenth Doctor himself to his final episodes, The End of Time. He knows that the prophecy has been made, spelling his doom when some mysterious figure 'knocks four times'. This, naturally, leads The Doctor to suspect that The Master, who has been plagued by the drumbeat of a Timelord's heartbeat forever, will be the cause of his death.

That leaves the Doctor initially running from his responsibilities, then coming to terms with what he's facing. As he crashes through the ceiling of the gate room, he faces both The Master and the Lord President Rassilon with a gun. As Rassilon raises his hand, he tells the Doctor that he is going to die along with the rest of them. The Doctor replies, "I know".

Only, he doesn't. The Master steps in, saving him, making everything right again. The Doctor begins to laugh in joy... until Wilf knocks, four times, on the glass of a radiation chamber. The look on Ten's face at that moment sinks faster than the soundtrack around them. He knows that, despite all of his efforts, his time is up.