Quotes / Perception Filter

Doctor: Don't run. Don't shout. Keep your voice down. Draw attention to yourself and the spell is broken. Just keep to the shadows.
Jack: Like ghosts.
Doctor: Yeah, that's what we are. Ghosts.
Doctor Who, "The Sound of Drums"

Forget the way you usually look at the world. This street's going to be hiding in plain sight. If you see something unusual or notable, dismiss it. Just keep walking. But if there's a bit of London so unremarkable that you don't even think about it... stop. You could very well be standing right outside a trap street.
The Doctor, Doctor Who, "Face the Raven"

Keep this up, and I could leave you bleeding to death in this lobby. A sprinkle of sand, and your body will sit here and rot. Your friends will hold their noses and step over your corpse, but you’ll remain here until the animals take you to pieces.
Fell, Pact
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