Love is blind — at least in the case of a wealthy Irish businessman who today pleaded with a judge not to jail his partner when she was sentenced to six years for hiring a hitman to kill him and his two sons.

Sharon Collins used the pseudonym “Lying Eyes” when she contracted a Las Vegas poker dealer to kill her partner PJ Howard, a property tycoon, and his sons Robert and Niall.

But in a bizarre twist during today’s sentencing in Dublin's Central Criminal Court, Mr Howard appealed for the judge to spare Collins, a 45-year-old divorcee with two children from a previous relationship, declaring: "I will not give up on Sharon".

The case has held Ireland in thrall as details emerged of Collins’s plot to kill her partner and sons — inspired apparently by his reluctance to marry her lest his self-made wealth, estimated to be €60 million (£48 million), was lost to his own children.

The couple met in 1998. When her efforts to persuade Mr Howard, 61, to tie the knot failed she bought a false marriage certificate from a Mexican website and succeeded in applying for an Irish passport in the name of Sharon Howard.

Believing that she had established her credentials she then made contact with "Tony Luciano" via another website, hitmanforhire.com. She sent Luciano €15,000 as a down payment on the murders.

Luciano was in fact Essam Eid, an Eqyptian working in Las Vegas as a poker dealer. In a series of e-mails exchanged between the Irishwoman and Eid, addressed from lyingeyes80@yahoo.ie to hire-hitman@yahoo.com, the two worked out a plan in which the deaths of Mr Howard and his sons would be made to look like accidental poisoning.

The sons would be poisoned in their local pub while their father would be pushed off the terrace of his Spanish holiday home, in an apparent suicide. Collins agreed to pay Eid $90,000 (£57,000) and bought flights for him and his wife.

But the plot unravelled when Eid arrived in Ireland, broke in to Robert Howard’s home and stole a laptop. He then contacted the victim, trying to blackmail him into paying €100,000 for the death contract to be lifted. Mr Howard contacted the police.

Eid was arrested and ricin was later found among his possessions.

Yet in spite of all the evidence against her, Mr Howard has refused to give up on his deadly lover. He kissed her on the lips at the end of giving his evidence, during which he said it was “very, very, very hard” to believe the charges against her.

He told of how she had cared for him in 2000 after a quadruple heart bypass operation.

Today he made an emotional appeal to keep her from being sent to prison, as she began a six-year prison term. He told the court, in a victim impact statement, that he would have no hesitation in living with Collins again.

That love was at odds with her own attitude towards the man who provided her with a luxury lakeside home in the west of Ireland, a luxury apartment on the Costa del Sol and a powerboat called Heartbeat.

Collins wrote to a popular radio DJ in 2005, accusing her partner of frequenting prostitutes, transvestites and swingers’ clubs in Spain and trying to persuade her to have sex with strangers.

Throughout the trial Collins maintained her innocence. Closing the case for the prosecution, Una Ni Raifeartaigh told the jury that from a distance the case may have looked like a cheap thriller but it was a tragedy for everyone involved.

"There might be a feeling abroad that at times there is a triviality about this case or a bewilderment because no one was actually killed," said Ms Ni Raifeartaigh.

"Ricin was found in the prison cell of Mr Eid and that takes this case out of fantasy and speculation. We are dealing with fools but we are dealing with dangerous fools."

This is unlikely to be the last that Ireland has heard of the odd couple. It has been reported that Collins has secured the help of a Los Angeles-based literary agent, after she told Ireland's director of public prosecutions: "I'll write a book yet".

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