The hiss became much more distinct. The room was dark, but she noticed an odd pattern of lights—colored LEDs—in the corner of the bedroom by the terrace doors. The light spilling over her shoulder from the bathroom showed an object at the foot of her bed that hadn’t been there when she’d come in a few minutes ago. It was a heavy industrial cart with fat tires. It carried a squat blue steel box with a control panel, currently dark, and thick loops of cable and hose. Standing behind that was a cylinder about her height, easily recognizable as one of the tanks used to contain industrial gases.

This was a welding cart. The steel box was the welding machine itself. The cylinder was the supply of inert gas used to keep the red-hot metal from oxidizing. And it was the source of the hissing noise. For the regulator had been unscrewed from the valve on the top, which had been opened. Hissing out of it and filling the room was gas.

Gas the entire point of which was that it did not include any oxygen.

She wasn’t woozy and light-headed because of heat but because she wasn’t getting enough air. She was being asphyxiated.

The welding cart was blocking her path to the terrace doors, so she headed for the cottage’s front door instead. But she drew up short when she saw that the way out had been blocked by several heavy items of furniture that had been dragged there and piled against it.

She spun back toward the glass doors that led onto the terrace and saw again the pattern of light she had noticed earlier. This time it was moving. It moved like a human. It was the Metatron. Its nighttime running lights had come on automatically. It had been standing near the glass doors. Now it was moving toward her. Another one just like it was moving outside. No, that was just the reflection of the first one in the glass. Spatial basics like in and out, up and down, vertical and horizontal, normally so intuitive, had become unfathomably tricky. She felt pressure on her knees and realized that she was in fact kneeling. More pressure on her shoulder was probably because she was slumped against a wall. The Metatron was coming toward her. She drew in a breath of 75 percent CO2/25 percent argon (that’s what the label on the hissing cylinder said) and called out “Help” in a strangely low syrupy voice. But the hissing had been reinforced by a heavy thudding noise that drowned everything out. She thought maybe it was her heart pounding but then knew it for a helicopter.