How we set about trapping chatroom 'groomers'
Long gone are the days when paedophiles hung around in children's playgrounds looking for victims.
The internet has opened a whole new world of opportunities for them - and dangers for our children.
As our team started to investigate this story it became clear that at the touch of a button, offenders could select, manipulate and abuse their victims from the comfort of their own home or office.
To catch a paedophile we had to think, sound and react like a 13-year-old girl, which included a crash course in text speak and what was hot or not in the world of boy bands.
Stream of filth
We quickly learned to expect the unexpected.
We set up a fake profile using an old photograph of a colleague.
"Emma" was 13, into JLS and hanging out with her mates.
In this distorted and dangerous online world "Emma", though just a schoolgirl, was quickly befriended by dozens of men.
With some there was no small talk - just a stream of filth.
A handful said they were teachers or office workers. A few happily chatted about their day jobs and their unsuspecting partners who were apparently cooking the dinner in the next room.
"Emma" was bombarded with sexually explicit messages.
From the first hello, some made it clear they wanted sex with children.
As the mother of a 13-year-old I found that hard - it's every parent's worst nightmare.
But in reality how many parents know about the risks their children are taking online?
As an adult, and a journalist I could see it for what it was. But I if had been a 13-year old girl like "Emma" I'd have been terrified and confused.
The dangers didn't just lie with the self-confessed perverts.
More disturbing were those who took the time to chat, to win "Emma's" confidence.
They showered her with compliments, asked about what music she liked. Of course, they all wanted photos and for her to go on webcam so that they could get to know her better. We'd been warned by a child protection expert not to.
Casually enquiring about where she kept her laptop and where Mum and Dad were they were constantly calculating the risks of being caught.
We tried gleaning as much information as possible from the "groomers" - anything that could help us identify them.
But these men live a lie. Their names and back stories are as fake as the feelings they professed to have for Emma.
We spotted one who had tried luring her to a hotel for sex, trawling a chat room for young boys to go on webcam when he thought she'd logged off. He was offering cash and the tragic thing is, he probably got what he wanted.
The toughest part of this investigation wasn't the stomach-churning conversations we had to have with men who wanted to abuse children.
It was knowing when we logged off they were still out there looking for more.
We've handed our evidence to the police.
Week In Week Out: Stranger Danger In Your Home is on Tuesday, 19 October at 2235 BST on BBC One Wales.