I turn my head, and you may go where you want.
I turn it again, and you'll stay till you rot.I have no face, but I live or die.
By my crooked teeth,Who am I?
This riddle was originally from Neil Gaiman's book Neverwhere.
You are
a key.
I turn my head, and you may go where you want.
You can turn a key to unlock a door.
I turn it again, and you'll stay till you rot.
You can also turn a key to lock a door.
I have no face, but I live or die. By my crooked teeth,
A key has "teeth" that fits its lock. If the teeth are damaged, the key will not work.