It was not an air purifier.

It was a portable cellular uplink camera, with its own power source and its own connection to the outside world, entirely independent of the house’s wifi, and I had set it up ten minutes earlier, in the quiet before I brought the tenants upstairs, in the brief window when Valerie thought I was simply using the bathroom.

I had learned, in my line of work, never to walk into a confrontation without first establishing a record that no one in the room could switch off.

That principle, establish a record no one can switch off, is the single most important thing my career taught me, and I have come to believe it reaches far beyond corporate fraud, into every situation where the powerful harm the vulnerable in private.