Detectives searching David MacBride's house found, tucked away in a desk drawer, a diagram of motor cruiser The Sundowner.

The scribbled lines were sketched by a hand which, days later, lifted an iron bar and brought it down again and again on Robert Saint's head.

For MacBride, The Sundowner was more than a boat: It represented escape.

He planned to sail to Spain, leaving behind his wife, family and dismally-failed life in which his only discernable achievement was a series of convictions for petty crime.

He became blinded by his obsession.

Within days of spotting an advert for the yacht in a broker's window at Birdham Pool, near Chichester, he committed the most brutal and cruel murder imaginable: The senseless battering of a kindly and popular grandfather, quietly living out his twilight years.

After two weeks listening to his preposterous pack of lies, it took a jury three and a half hours to reach a unanimous guilty verdict.

Jailing him for life, the judge described Mr Saint's death as perhaps the most open-and-shut case of murder he had ever come across.

MacBride was born and raised in Colchester, Essex, and left school aged 16 to train as a mechanic.

He worked in the building trade and later got his first taste of ocean life as a merchant seaman on board a coaster.

He lived on the fringes of the law but was not a successful crook.

In 1985 he was convicted and fined for deception and theft after hiring building equipment and selling it at auction.

In 1992 he was back before the court, this time for stealing a driving licence.

He married and had four children but moved to West Sussex eight years ago after the couple split, landing a job as train conductor. He remarried in 1997 to Catherine, becoming step-father to her two children. The family lived in Bramber Close, Bognor.

But he became restless, consumed by dreams of pulling off the one crime that would set him free.

In the weeks before his path crossed fatally with Mr Saint's, MacBride spoke to friends about living abroad.

One said: "That summed him up - grandiose dreams, fantasies and no money. But I never thought he was capable of killing."

Mr Saint had put his pride and joy on the market for £119,000, partly because it brought back too many memories of his late wife.

With a low-paid job and a family to support, there was never any question of MacBride being able to afford such a rich man's toy.

But poverty was no obstacle. MacBride had £75,000 debts and the only currency at his disposal was violence.

After his first attempt to pay for the boat failed, when a dud cheque bounced, he lured Mr Saint into a taking him out for a sailing lesson on September 25 last year. As the land dipped out of sight, he killed him.

Police later found the boat at Itchenor, discovered bloodstains and launched a murder inquiry.

Mr Saint's body was found ten days later near Sandown on the Isle of Wight.

Police believe MacBride hit him with a heavy blunt weapon, possibly a starting handle, 16 times on the head before dumping the body and the weapon over board.

When MacBride was questioned by police, in the days after Mr Saint's body washed up on a beach on the Isle of Wight, he fed them a story so far-fetched and bizarre it beggared belief.

Straight-faced and calm, he told detectives how he had found a holdall stuffed with used £50 notes on a train.

It was a story which, having no other possible means of explaining the purchase, he stuck to doggedly in court.

He also concocted fantasies about Mr Saint's death: First, how he had dropped off Mr Saint in Portsmouth before his disappearance and then how Mr Saint had banged his head on board during a sea swell.

But the jury saw through his wafer-thin lies.

Detectives Chief Inspector Tony O'Donnell, who led the inquiry, said he was satisfied with the trial's outcome.

He said of MacBride: "His crime was a callous act of greed and violence and I am pleased the jury came to the correct and proper verdict."