The Vault Door

You're ready as you are now. You walk over to the vault door and pull on the crank. It doesn't budge at first. You lean into it, tugging and swearing. Finally, with an ear-splitting shriek, the metal yields and the crank turns. The bolts slowly retract into the door with each turn of the crank until finally you are able to pull the door open. You step through to the other side. There's a concrete tunnel beyond, leading to a set of wooden double doors. That's all you see before the automatic lights in the bunker behind you shut off and the vault door swings closed.

It's pitch black.