Robert Napper

Fingerprints left at the scene identified Robert Knapper as the depraved killer, but it wasn't until a cold case review of Rachel Nickell's murder that DNA evidence finally led to Knapper's conviction in 2008 for one of Britain's most notorious crimes.

There is something about Napa that still to this day sends a shiver down my spine.

In that sense, he is a satanic figure.

This killer's story began on the 25th of February, 1966.

The other children seemed to have got over it quite well, but Robert Knapper continued to display behaviour which was unusual for a child of his age.

At one point, he turned to his father and said, they think I'm mad.

His father thought it was a joke, but the awful truth, the reality, is that Napa probably realized, even at a very young age, that he had the capacity for something quite extraordinary.

At the age of 12, his parents divorced and his father left the home.

Because Robert Knapper wasn't finished.

On the 3rd of November 1993, while Colin Stagg was still in prison on remand for the murder he did not commit, Robert Napper would break into a flat in Plumstead.

Inside was a young woman named Samantha Bissett, who was 27 and originally from Dundee, as well as her four-year-old daughter, Jasmine.

Napper murdered them both.

The level of violence used is absolutely horrific, and it's something that really did shock the nation to the core.

The depraved killer was 26-year-old Robert Napper.

16 months later, he would strike again, killing a four-year-old child, Jasmine Bissett, and her 27-year-old mother, Samantha, who was brutally dismembered.

Leaving a woman posed in a way that robbed her of dignity, that is beyond simply wanting rid of somebody.

That is truly evil.

Robert Napper was a rapist who sadistically attacked mothers in front of their children.

He brutally killed two women, then desecrated their bodies, making Robert Napper one of the world's most evil killers.

When Rachel Nickell's murder hit the news, the public were appalled.

Now, that's quite a charge sheet, isn't it? Podmore, though, denied all the allegations, which meant the case went to trial at Cardiff Crown Court in the late summer of 2001.

The jury consisted of eight women and four men, and the trial was presided over by Judge Griffith Williams, an experienced judge who would later go on to preside over several extremely high-profile murder trials, including those involving the murder of April Jones and the serial killers John Cooper and Robert Napper.

The court heard from the 26-year-old woman who had been subjected to this terror at the hands of Podmore, and she told what had happened to her during her spell of imprisonment, including the electric shocks and the threats made against her.

She told the court that wires had been attached to her body and that Podmore had switched electricity on and off before telling her that if he left it on for longer, this would kill her.

He'd also been linked previously to a series of attacks on women that became known as the Green Chain Rapes.

What followed was the case after the case, the damage to Colin Stagg, missed opportunities around Napa and Bill Clegg QC's unusual position in both parts of this story.

Bill had defended Colin Stagg.

He later represented Napa in the Samantha and Jasmine Bissett case.

Reading the file papers on Napa, he became convinced that the same man had killed Rachel Nickell.

But it took the police a lot longer to make that connection.

So this was a story about forensic science catching up, but also about assumptions, tunnel vision, and the lives affected when an investigation went in the wrong direction.

Well, it would have done if Colin Stagg had been convicted.

Re-examining crimes so shocking they still haunt our imaginations.

In the last episode, looking back at the murder of Rachel Nickell in 1992, we heard how a court stopped the wrong man being put on trial and potentially convicted.

But when Colin Stagg walked out of the Old Bailey a free man in September 1994, Rachel Nickell's killer was still unidentified.

By then, Robert Knapper had already killed again.

While Stagg was in prison on remand for Rachel's murder, Knapper killed Samantha Bissett and her four-year-old daughter Jasmine in Plumstead, south-east London.

He'd also been linked previously to a series of attacks on women that became known as the Green Chain Rapes.

What followed was the case after the case, the damage to Colin Stagg, missed opportunities around Napa and Bill Clegg QC's unusual position in both parts of this story.

Bill had defended Colin Stagg.

Jasmine was sexually assaulted and smothered to death.

The man identified and convicted of those murders was Robert Napper.

In 2006, 24 years after Rachel's murder, Napper was linked to her killing using DNA techniques not available at the time of the initial investigation.

Napper was subsequently charged and convicted of killing Rachel, although this was manslaughter by diminished responsibility rather than murder.