The Doctor nods and presses onwards down the right corridor when the lights shut off, leaving them completely in the dark.

Fishing through his pockets, the Doctor manages to find a torch, but stands completely still for a second, before tilting his head back. "I don't suppose that's you touching my leg?"

It started at his ankle, then his calf, rising higher and higher. Quickly, he flashes the light on his leg to find a snake slithering upwards. "Where did you come from!?"