‘Ingenious actually,’ Beck replied. ‘The instructions were essentially plugging the box into a power outlet and then connecting the box with the camera to the internet. He could remotely track their movements without them being any the wiser, and no one ever thought to take the box apart and look inside as they looked like standard cable boxes. He wrote all about it in his last journal. He’d taken immense pleasure in the fact that he was able to lure these women into doing his bidding by their own greed, that a measly fifty dollars a month was enough to allow him into their lives.’

‘Jesus,’ I said under my breath. ‘Honestly, these women were college students and they were probably broke. I can’t say if Andie and I got that offer that we wouldn’t take it too, even now that we’re out of college. I know it doesn’t seem like much but when you’re just barely able to make rent and bills, fifty dollars would seem like a Godsend for doing nothing.’

‘Well, that was what he was banking on. And it worked,’ Hannigan concluded.

‘Wait, there’s one thing that doesn’t track here. Frank was never good with electronics. I was always better at that and he’d call me over to his house to fix things all the time. I just can’t see him having the knowledge to accomplish something like this.’

Hannigan looked long and hard at Cris, and then glanced at Beck. ‘There’s no way to know since the journals ended after he switched methods but maybe he read a book or looked it up online. It’s possible he learned how to do this one thing that he needed to carry out his mission. When a killer like Frank is motivated, they’ll go to any length to make sure they’re able to keep killing.’

Cris looked unconvinced but didn’t say anything. I didn’t know Frank to form an opinion on the matter but it seemed possible he had taught himself what to do. He was obviously intelligent if he’d gotten away with murdering women for over forty years.

‘What about the photo from the cabin? Do we know who that other young boy is then, since it isn’t Cris?’ I asked, looking at Hannigan. He pulled the photo out of the file that I had handed over at the scene and placed it on the table.