But as she closed the manual, a cold thought arrived. On page 33, a small note: “The beam cannot see around corners. It protects a line, not a volume. Use multiple units for complex spaces.”

In the fluorescent hum of a warehouse storage unit, nestled between a box of obsolete VGA cables and a deflated inflatable Santa, lay a document of quiet power: the .

She unzipped her toolkit, pulled out the spiral-bound manual, and began to read.