Night Stalker accused Delroy Grant’s claim that his ex-wife planted his DNA to frame him for sex attacks was branded as “pure fiction and fantasy”, a jury heard today.

Grant, who is said to have carried out a string of attacks and burglaries on elderly victims over the course of 17 years, alleges Janet Watson used a male accomplice to commit the offences and set him up.

The 53-year-old says during their marriage Ms Watson, who divorced him in 1979, made him give samples of his semen and saliva to get him tested for an STD after she discovered he had been with another woman.

Father-of-eight Grant, of Brockley Mews, Brockley, told Woolwich Crown Court she was motivated by “malice” and “hatred” of him.

Jonathan Laidlaw QC, prosecuting, said: “Your defence that someone planted your DNA is a lie borne out of desperation and because you have a complete inability to face up to what you have done.

“You simply refuse to face up to the burglaries and to the old people you have raped and attacked over the best part of 20 years.

“The idea that Janet Watson, who has already suffered at your hands, was behind this elaborate scheme to frame you is, the prosecution suggest, pure fiction and fantasy invented by you from start to finish.”

Mr Laidlaw quizzed Grant as to why he made no mention of his defence to police when he was arrested in November 2009.

When asked why he did not mention his claim that his ex-wife had collected samples of his semen, Grant said: “I just did not link the two at the time.”

Mr Laidlaw said: “As you sat there during day after day of interviews, are you telling the jury it didn’t cross your mind she was behind this?”

The prosecution claimed Grant’s defence was something he had “made up” since his arrest because he could not “face up to the enormity” of what he had done.

Grant replied: “For what reason would I want to rape old women?”, to which Mr Laidlaw said: “That’s a very good question”.

Mr Laidlaw said: “If these charges weren’t so grave, this would be almost laughable as an account.”

He added: “Ms Watson is not behind all these offences. She had a bad time at your hands when you and her were together.

“You were the softly spoken charmer. Once you were married you treated her badly.

“The truth is Ms Watson didn’t want to have anything to do with you as of 1979.

“The truth is she’s a thoroughly decent, hard-working mother, who has had absolutely nothing to do with seeking to get you into trouble in the years that have passed.”

When Grant was arrested in Witham Road, Beckenham, the prosecution allege he was caught “almost red-handed”.

Grant was found wearing two pairs of jeans and three t-shirts, which the defendant explained was because he had been decorating and also because it was cold.

He claims a torch found in his pocket was planted by police and that the crowbar found in his Vauxhall Zafira was put there by Ms Watson’s accomplice.

Mr Laidlaw said: “The luck you had had for the best part of 20 years was about to run out.

“You say it’s not just Ms Watson and her accomplice but that the police have also indulged in this planting things on you.

He added: “You have become a very sophisticated rapist and burglar by this stage.

“You knew the police were after you and if you used ATM machines there would be cameras, that’s why you had a variety of clothes available to you and changes of footwear.”

Grant denies a total of 29 offences between 1992 and 2009 including 16 burglaries, two attempted burglaries, three rapes, one attempted rape, six indecent assaults and one sexual assault.

The trial continues.