I just re-watched this, yesterday, and something happened that made me wonder. Here's the scenario: You're the Doctor and you're at the mouth of the Jeffries Tube. The corridor is about to explode into space, but 2 ensigns are trying to get to the tube. In the episode, the Doctor closes the door when he realizes that he can't save them. However, this time it's you and instead of 2 ensigns it's your best friend and YOUR child. What do you do? EDITED for clarity.