But I think she means something to do with whatever is behind the iron door.

He could now open and close the iron door at will.

Then he found himself in a hall, which had an iron door at one end.

At the top of the stone steps was an iron door.

She came close and waited, with her face to the iron door.

The iron door was standing about an inch and a half open.

The ring of police had reached the small iron door.

The iron door through which we had passed a few minutes ago was now locked.

Shut the iron doors on the past and the future.

They walked a mile and came to a white wall with a black iron door at the center.