The Dentist

You wake up from a dreamless sleep, lying on the floor in the last place anyone wants to find themselves: the dentist's office. You shake yourselves properly awake, and struggle to remember. You're quite sure you came in for some standard outpatient work, but despite the lack of windows, you have a strong intuition that it's night time. Something must have gone wrong. You quickly reach up to your mouths, but you feel no pain, no creepy post-anaesthetic numbness, not even any gauze stuffed against your gums. It's like no procedure was done on you at all. But you definitely remember Doctor Stephens lying you down in the chair and sticking a gas mask to your face...