It fitted, and he opened the box, but after a moment's hesitation, closed and relocked it, and slipped the bunch of keys, as well as the key that had originally stood in the lock, into his own pocket. 
He didn't anyone to know what was in the box.
mnli hypothesis: He didn't anyone to know what was in the box. premise: It fitted, and he opened the box, but after a moment's hesitation, closed and relocked it, and slipped the bunch of keys, as well as the key that had originally stood in the lock, into his own pocket. 