Gavin Plumb, 37, allegedly hatched the "graphic" and "sexually motivated" plans over more than two years as he tried to recruit accomplices online.

Chelmsford Crown Court heard he boasted of trying to abduct two air hostesses from trains and falsely imprisoning two 16-year-old girls to "bolster his credibility".

Killing Willoughby was suspect's 'ultimate fantasy', court told | Trial as it happened

Prosecutors allege his past convictions - which included tying a teenager's hands behind her back with rope and tape, and using an imitation firearm - showed he knew "what it would take to terrify and overpower a woman".

But Plumb, from Harlow, in Essex, unwittingly disclosed his plans to an undercover US police officer, who alerted the authorities in the UK and disrupted his plans to carry out "catastrophic violence" against Willoughby, the court heard.

A jury was told he had more than 10,000 images of the former This Morning host on his mobile phone when he was arrested in October last year, while officers found two sealed bottles of chloroform, along with a "kidnap kit".

Police also found "a list of celebrities" in his bedside drawer, along with folded-up images of famous people, including Willoughby, on top of his wardrobe.

Plumb, who appeared in the dock wearing a light grey sweater and dark tracksuit bottoms, denies charges of soliciting murder, incitement to kidnap and incitement to rape between December 2021 and October last year.

Willoughby, who is not attending the trial, has waived her automatic right to anonymity, which all alleged victims of sexual offences or related charges are entitled to.

The 43-year-old announced in October last year that she was stepping down from This Morning after 14 years on the ITV show, but has since hosted Dancing On Ice 2024, and is to present a Netflix show.

Jurors were told she has never met Plumb, who had been planning an attack on her for "some time", talking with an online contact, Marc, who is believed to have been based in Ireland, about launching a "home invasion" as far back as 2021.

They shared "deep fake" pornographic images of Willoughby as well as images of her home, the court heard.

Plumb later discussed trying to get on to a tour of the ITV studios to get close to her or using his training as a security guard to get a job protecting her, prosecutors said.

Plumb also shared a picture of an empty space or "dungeon" that he said was "big enough for a bed", while Marc said her "screams could not be heard for miles", prosecutor Alison Morgan KC said.

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"It was not just the ramblings of a fantasist," she said. "The defendant had carefully planned what he would do and how he would do it, purchasing items that would assist him in carrying out the attack."

But when his plans did not move forward in the way he had hoped, he began unwittingly talking to a US undercover police officer referred to as David Nelson in October last year, the court heard.

The officer, from the Owatonna Police Department, in Minnesota, was monitoring an online group called "Abduct lovers" involving chats about kidnap, torture and murder.

Calling himself "BigBear", Plumb posted pictures of Willoughby and said he had a "load of info" on her, including when she has security and "what time she gets up in the morning", the court heard.

When asked if he was serious, Plumb shared a video, which was played in court, showing items laid out on his bed including hand and ankle shackles, a ball gag, rope, metal cable ties, and two sets of handcuffs.

In other messages, he described the plan to use chloroform on her and her husband, the television producer Dan Baldwin, before tying her up and kidnapping Willoughby.

When asked what will happen at the end, Plumb said: "Slit her throat, clear her out and dispose of it," the jury was told.

The undercover officer alerted the FBI and UK police, who arrested Plumb over an alleged conspiracy to kidnap Willoughby.

Officers said he was "shocked" but said: "I'm not gonna lie. She is a fantasy of mine."

Ms Morgan said it is likely Plumb may suggest "this is all just a fantasy" during his trial, but she asked jurors if the messages he exchanged with others are the "talk of a fantasist" or if the "dark depravity" suggests he meant what he said.

The trial, which is expected to last for two weeks, continues.