The detective, glowering at the other, pulled aside curtains, peered into corners; then made furious and fruitless search of the rooms below, bringing up at last at Maggie's door, which the Duchess had slipped ahead of him and locked.

When he demanded the key, the Duchess told him of Maggie's departure and her carrying the key with her.

It was a solid door, with strong lock and hinges; and two minutes of Gavegan's battering shoulders were required to make it yield entrance.

Not till he found the room empty did Gavegan think of the trap and the roof.
Larry made good use of these few extra minutes granted him.

Whatever he was to do he realized he must do it quickly.