The BBC drama is based on the harrowing true story of the Rochdale grooming scandal.
At least 47 young and vulnerable girls were raped, trafficked and abused by a gang of predominantly Pakistani men – nine of whom were jailed in 2012 for a range of child sex offences.
Tonight’s episode introduces Margaret Oliver (Lesley Sharp), a detective constable for Greater Manchester Police (GMP) who eventually resigned over the Rochdale grooming scandal.
Who is Margaret Oliver?
Margaret was assigned as witness manager to two girls who between them said that they had been abused by 20 different men in Rochdale.
“I went to them and I convinced them that they are victims of these men, I convinced them that we needed them as witnesses to protect other victims from these same men,” she told the BBC in 2013.
“They put their trust in me, I put my trust in GMP to honour those obligations.”
When she learned that the Crown Prosecution Service had decided not to call one of the girls as a witness, Margaret said that she felt “ashamed” to be a police officer.
“I feel that had the full facts been heard from the girls, we would have got heavier sentences and there wouldn’t be offenders still walking the streets of Rochdale,” she said.
The mother-of-four resigned from her job of 15 years in October 2012. She said that she was concerned that allegations of sexual abuse were not being recorded by police.
“I’ve walked away from a career that I love because I believe so strongly that 10 years down the line, when somebody turns around and says ‘why did nobody speak out about this’ I can look in the mirror and known that I have done the right thing,” she said.
Five years on, ahead of the launch of Three Girls, Margaret told The Guardian: “I tried with every ounce of my determination to highlight to the chief constable and all the agencies – the IPCC, the children’s commissioner, the Home Office select committee – what was going on, but without success.
“No one really wanted to hear what I was saying and eventually I was left with a stark choice.”
In 2015, GMP acknowledged that “mistakes were made and victims let down” in the Rochdale investigation, and apologised to the victims.
The force looked at the conduct of 13 officers between 2008 and 2010 and served notices of misconduct on seven.
One of those officers was set to face disciplinary action, but was allowed to retire any sanctions could be imposed.
Margaret revealed that she is still in contact with some of the victims who say that many of their abusers remain free men.
“I’m speaking to kids who are telling me that even to this day they are seeing offenders that they’ve named, walking around Rochdale,” she said.
“Somebody saw one in London, another person told me that one has moved around the corner from her.
“That’s why I’m saying things haven’t changed, because those men have been named by those girls and I know that they’re still out there walking around.”