The detective glanced around the room with a practiced eye and then looked blandly back at the little Scotsman. Harry MacDougal was lying, and the sergeant knew it. And Harry knew the sergeant knew it.
Sergeant Cowder sighed for a third time and looked at the Scot. “Okay. So what happened?”
Harry’s face became serious. “They came in about six-thirty. First I knew of it, one of the kids—the boy—stepped out of that closet over there and put a vibroblade at my back. I’d come back here to get a small resistor, and all of a sudden there he was.”
Mike the Angel frowned, but he didn’t say anything.
“None of your equipment registered anything?” asked the detective.
“Not a thing, Sergeant,” said Harry. “They’ve got something new, all right. The kid must ha’ come in through the back door, there. And I’d ha’ been willin’ to bet ma life that no human bein’ could ha’ walked in here without ma knowin’ it before he got within ten feet o’ that door. Look.”
He got up, walked over to the back door, and opened it. It opened into what looked at first to be a totally dark room. Then the sergeant saw that there was a dead-black wall a few feet from the open door.
“That’s a light trap,” said Harry. “Same as they have in photographic darkrooms. To get from this door to the outer door that leads into the alley, you got to turn two corners and walk about thirty feet. Even I, masel’, couldn’t walk through it without settin’ off half a dozen alarms. Any kind of light would set off the bugs; so would the heat radiation from the human body.”
“How about the front?” Sergeant Cowder asked. “Anyone could get in from the front.”
Harry’s grin became grim. “Not unless I go with ’em. And not even then if I don’t want ’em to.”