Pavarotti was playing on the CD player inside the Jaguar XJ6 as it pulled up at the scene where Jane Longhurst's body was found.

Police and scenes-of-crime officers stopped briefly as the Italian love songs broke over the morbid scene.

Stepping from the car was Steve Dennis, an avid fan of Inspector Morse, the TV detective who also loved classical music and drove an old-style Jag.

The detective chief inspector, in charge of Operation Keen, sported his usual neat moustache and crisp suit as he approached.

He has a lot in common with Morse: He likes a pint, expensive wines and the finer things in life and says he appreciates the more subtle approach to crime detecting as practised by the late John Thaw's character.

There is one more similarity. Like Morse, he usually gets his man.

The 53-year-old married father of three daughters has chalked up a 100 per cent detection rate since joining the Sussex Police Major Crime Branch two years ago.

Not that cracking this case was a one-man job, or especially demanding once Jane's body was discovered.

He is quick to credit his deputy, Detective Inspector Chris Standard, and the Operation Keen team.

It started like a mystery straight out of the Morse series.

Jane vanished without trace from her home in Shaftesbury Road, Brighton, on Friday, March 14 last year.

She lived in a ground-floor flat with her partner of four years, Malcolm Sentance, and was happy, healthy and financially sound.

Police found nothing to suggest Jane had any love interests outside her relationship with Mr Sentance.

There were no phone records, no text messages, no rumours.

The night before she disappeared, Jane and her partner spoke about buying paint to decorate a rear wall and discussed selling up and moving to the Bath area.

They were content, although Jane showed mild frustration with Mr Sentance for his reluctance to get married and start a family.

An accomplished musician, Jane was practising for a concert the following weekend.

She had every Friday off from her teaching job at Uplands School in Hollingdean, Brighton, and that particular Friday she kissed Mr Sentance goodbye as normal.

She was relaxed and seemed perfectly happy with life. Friends she called that morning said she seemed her normal bubbly self.

It made her disappearance all the more baffling.

Most people who go missing return or are found safe within hours and at first police were not overly concerned.

Alarm bells rang at Brighton police station the following Monday when she still had not turned up.

Bells also rang in The Argus newsroom.

I interviewed Mr Sentance, Jane's mother Liz Longhurst and Jane's sister Sue Barnett and it was immediately apparent this was no ordinary disappearance.

Her relatives were at a complete loss. This was not the Jane they knew.

She had never disappeared and this was completely out of character. She wasn't answering her mobile phone and she had left behind all her clothes and belongings.

The Argus made it the front-page main story that night and the next day police said they were treating Jane's disappearance as a crime.

Officers carried out house-to-house inquiries and were initially thrown off track by a neighbour who thought she had seen Jane entering her home carrying shopping bags that Friday afternoon.

A Home Office forensic profiler suggested possible sites for police to search and officers combed every back yard and garden around Shaftesbury Road and later open ground on Ashdown Forest.

Malcolm gave detectives a list of all their friends and relatives and officers started interviewing them.

One friend, Lisa Stephens, a schoolteacher, lived with Graham Coutts in Waterloo Street, Hove.

Phone records showed Miss Longhurst's last call, at 10.05am, was to Miss Stephens' home. Lisa was out but Coutts answered.

Coutts confirmed to police in two interviews that he had spoken to Miss Longhurst and said they had nothing more than a general conversation about Lisa's pregnancy.

Coutts remained on the police active list but he was not seen again until after Jane's body was discovered on April 19, a total of 35 days after she had disappeared.

A man out driving found the burning body on a track south of the A283 at an RSPB nature reserve at Wiggonholt Common, near Pulborough.

It was a scene everyone had dreaded but Mr Dennis and the team got to work gathering evidence.

Traces of petrol and, more importantly, the remains of a cardboard box with the word "fragile" stamped on it were discovered round the body.

Five days later Detective Constable Debbie Upton spotted boxes in Coutts' lounge marked with the same word. The connection was made.

Under the body police discovered more clues - a blue plastic tarpaulin and cardboard with the word Kleeneze, the door-to-door firm Coutts worked for.

The following day Home Office pathologist Dr Vesna Djurovic removed a ligature made from women's tights from around Jane's neck and confirmed she had died from strangulation.

Decomposition suggested she may have been dead for four to five weeks and had been stored in a cool place away from insects such as flies.

Jane was naked apart from a green woollen scarf round her face and a box over her head.

Detectives went back to re-interview suspects and on the evening of April 24 Coutts was seen again at his home.

Coutts said he had been delivering cleaning products in Hove on the night Jane was found but could not remember addresses.

He said he had picked up catalogues but again couldn't recall where and he was unable to produce receipts to verify his movements.

Coutts was arrested on suspicion of murder. He made no admissions and he was released on bail the next day, April 25.

Three days later police received a call that sealed the case. Staff at the Big Yellow Self Storage warehouse in Coombe Road, Brighton, were concerned about a person who had rented a small container from March 25.

Coutts had used the name Paul Kelly, Kelly being the name of an old school friend. Using his computer, he had forged the name on to an old water bill to use as proof of identity.

Big Yellow staff noticed a dreadful smell coming from Coutts' container and thought it was dead pigeons. The smell had dissipated when Coutts removed the box containing the body.

The man who called police was nervous and told officers he hoped he wasn't wasting their time.

Far from it. When police viewed Big Yellow's CCTV footage they instantly recognised "Paul Kelly" as Coutts. The footage showed he had visited unit C50 seven times between putting Jane in there and removing her. All visits were short.

On April 18, the day before the body was found, Coutts was filmed entering at 6.45pm and leaving at 7.04pm, wheeling out a large box on a trolley.

The footage made gruesome viewing for the jury.

Out of shot, Coutts loads the body into his Rover car but minutes later is seen entering the Big Yellow lift and glancing over his shoulder at something on the floor.

He walks to a toilet and returns with a paper towel. He wipes from the floor what police believe is body fluid that had leaked from the box.

Mr Dennis said the evidence began to slot into place "like a jigsaw".

A key seized from Coutts fitted a padlock on unit C50 and inside the police found Jane's clothes and belongings and Coutts' blood-stained shirt.

Coutts was re-arrested on the evening of April 28 and charged the next day.

He said nothing to police but his computer spoke volumes. It revealed thousands of images of female strangulation and necrophilia downloaded before and after Jane's death.

Police checked with a petrol station, Texaco in Kingsway, Hove, and CCTV footage showed Coutts buying a petrol can, toilet tissues and roll of black tape at 7.40pm on April 19, just 20 to 30 minutes before Jane's body was found.

Crucial to the case was evidence of strangulation sex provided by Coutts' ex-girlfriends Sandra Gates and Nicola Stainthorpe. They testified behind screens that they had not enjoyed the sessions but wanted to please Coutts.

He had wanted one to black out and remain still, as if dead.

Mr Dennis said: "They were very brave in coming forward. There was huge pressure on them and both were distressed having to give intimate details."

Mr Dennis expressed some sympathy for Coutts' partner: "Lisa Stephens is very upset. She has just had his children and was expecting a nice cosy lifestyle for them."

Of Jane, he said: "She was a very nice person and everyone loved her. She was a schoolteacher who gave her life to children...she was loved by everybody."

And of Coutts: "I have no words to describe him."

Detective Constable Dick Bidmead, part of Operation Keen, added: "There are occasions when you think you've hit the bottom of the well of depravity. Then you realise the stone is still falling."

The Big Yellow Self Storage warehouse has permanently sealed unit C50, where Coutts kept Jane's body. A spokesman said this had been done as a mark of respect for Jane.