She got to her feet, crouching to stay low, and walked as quietly as possible to the side of the house. She knelt and touched the surface. It was concrete, and this side of it felt cool. It would be impossible to cut or breach in any way. Firing at it would accomplish nothing. She moved around the building, and the only windows she saw were the same—high up and only about four inches wide. The glass was thick, set in steel frames with latches like the ones on basement windows. She kept going around to the front. The door was as it had seemed in the drone’s camera—steel rods over steel plates.

She passed the front steps and saw more of the long, narrow windows, all of them closed and latched. As she reached the third side, she still saw nothing that would admit an intruder. Everything was high and narrow and unreachable. She kept moving and turned the corner to the rear of the house.

She saw the two large, white propane tanks at the back of the house. One of them was hooked up to a hot-water heater with a flexible braided half-inch hose. The other was fitted with the same kind of valve and the same kind of hose. The hose went into a conduit made of a length of pipe that had been set into the concrete when it was poured. She looked up and saw that almost eight feet up was a flat, hinged vent cover set into the wall, the kind used in kitchens. There must be a stove and a hood inside, and they must be using propane to fuel the stove.

Leah knelt and turned off the two valves on the tanks. Then she took out the Ka-Bar knife and cut both of the hoses. She pulled out the severed end of the hose leading from the kitchen and set it aside. Then she pushed the remaining length of the hose from the propane tank back through the pipe into the kitchen. She pushed until the hose moved easily into the space, and then she opened the valve on the propane tank.

Next she examined the hot-water heater. Two copper pipes were inserted through other openings built into the concrete wall, one for the lukewarm water supply from the house and another for the heated water flowing back into the house. The copper pipes were a bit smaller than the holes in the wall, and the extra space was packed with rags. She pulled the rags out, cut the hose that went from the propane tank to the hot-water heater, and then stuffed that hose into the opening beside the pipe for the cool water and refilled the extra space with rags. Then she turned on the second propane tank.