Anything else might end behind a wall or under a floor.
He looked up at the house that sat behind the wall.
"Attack now or rest the night behind our wall of fire and take the battle to them in the morning?"
"There must be a lot of history behind their walls."
That means you have to attack them behind their walls.
The kitchen remains in the center, but these days most of it is behind a wall.
He told me about an old school behind a high wall in a dirty street.
I'll take you to some of the other Sisters behind the wall.
I was behind the wall and went into the garage.
The man was back behind the wall the moment he'd fired.