Doctor Who: 10 Terrifying Moments In Under The Lake
7. Back To Night Mode
Don't be afraid of the dark you tell yourself but in Under The Lake that is precisely when the ghosts come. So it is a relief when daylight mode switches on and the Doctor, Clara and the terrified crew can get to work investigating the problem and finding a way off the base.
Except then the ghosts find a way to switch the base back to night mode. As the lights go off and the tunnels are plunged into darkness the enemy gains the upper hand. You can feel the tension as the crew races against time to grab their supplies and race back to the one safe part of the base keeping the ghosts out. This time, the darkness really could be the death of you.