A bleak film which tells the story of how teenager Kayleigh Haywood was groomed online by a stranger and then brutally raped and murdered has been released by police.
The film, called Kayleigh's Love Story, charts the last fortnight of her life and warns parents and children of the dangers of online grooming.
Kayleigh, 15, was killed by Stephen Beadman in November 2015 after being bombarded with messages on Facebook and other social media sites for around two weeks by his 28-year-old neighbour Luke Harlow.
Over a fortnight, they exchanged 2,643 messages.
Harlow groomed Kayleigh, along with two other girls he had also been speaking to, but it was Kayleigh who finally agreed to his requests to spend the night at his house.
The five-minute short was made with the support of Kayleigh's parents and has already been shown at schools in Leicestershire and Rutland.
Leicestershire Police said 35 children found the courage to come forward and report possible cases of grooming to officers after seeing the film.
The award-winning film, which begins with a warning that it would have a 15 certificate if shown in a cinema, starts by showing how Kayleigh began receiving messages from Harlow.
As the pair exchange messages, the film cuts between scenes of Kayleigh at home with her family and Harlow smoking a cigarette in his flat.
It also shows examples of messages Harlow sent the teenage girl as he groomed her.
"Mum and dad wouldn't understand, they don't know that he's different," the actress playing Kayleigh says.
The film shows Kayleigh meeting Harlow at his house on Friday 13 November, where she spent the next day.
In the early hours of Sunday 15 November, having been held against her will by Harlow and his next door neighbour Stephen Beadman, Kayleigh was raped and murdered by Beadman.
The video ends by warning: "Stop and think. When you meet someone online, you don't always know who you are talking to."
The film was shot in various locations across Leicestershire and Nottingham by Affixxius Films.
Miles Latham, managing partner of Affixxius Films, told The Independent: "It is one of the most intricate projects we have ever taken on. The production of a film this graphically accurate, while the case was still going on, is unheard of.
"Very few police forces would have the courage to get the family's permission. There were obvious difficulties having to work with Kayleigh's mum and dad, which was incredibly difficult.
"They were obviously broken, hollow people. But to give them enormous credit, they were one hundred per cent behind the project from the beginning. They endorsed the film wholeheartedly."
He said the video agency wanted to capture the character of Kayleigh in the film. "We wanted her to walk like Kayleigh, to move like Kayleigh, to interact with her family like Kayleigh did."
Leicestershire Police gave them access to all of the digital messages exchanged between Kayleigh and Harlow, allowing them to build their script. "It's like reading something out of a horror film," Mr Latham said.
He said he hoped the film would "reinforce a message which is as old as time: Don't talk to strangers.
"The only way we can stop other incidences like Kayleigh's happening is if young adults have a moment of realisation and are able to realise that things could develop."
Leicestershire's Deputy Chief Constable Roger Bannister said: "What happened to Kayleigh was horrific but we are pleased that some good is coming from the awful tragedy and that this film is raising far greater awareness of the dangers of online grooming and the signs that it may be happening."
Last July, Beadman, then 29, was sentenced to life imprisonment for the rape, false imprisonment and murder of the teenager, while Harlow was given a 12-year jail term for false imprisonment and grooming.