A Minnesota detective’s routine monitoring of a crime-infested chatroom led to the arrest and conviction of a U.K. man who made plans to stalk and murder popular English TV personality Holly Willoughby.

In October 2023, the detective had been looking into an online chat called “Abduct Lovers” through Kik, an instant messaging app that allows users to remain anonymous. Using the alias David Nelson, he uncovered 37-year-old Gavin Plumb’s violent plot to kidnap and murder Willoughby.

“This work requires a creative ability to engage in online chats to build trust and a willingness to maintain an online presence,” Owatonna Police Chief Jeff Mundale told Fox News Digital. “While these online investigations are just part of this detective’s regular work, it is due to a strong commitment to and interest in working covert cases across various social media platforms that led to this case being discovered.”

The detective’s work typically involves sex-trafficking cases involving minors, as well as rape-for-hire and illegal firearms transaction cases, Mundale noted.

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“Upon recognizing imminent danger to Willoughby, the detective alerted FBI authorities who contacted London Metropolitan Police and Essex Police,” Mundale said. “The coordination and quick action by law enforcement officials in both countries demonstrate the gravity of this situation and the effective teamwork this case presents.”

“The brilliant work of our detective and his impact on saving lives and preventing future victimization of others is immeasurable.”

— Jeff Mundale, Owatonna police chief

U.K. authorities on July 4 thanked the Minnesota officer’s undercover work after Plumb, of Potters Field, Harlow, was convicted of soliciting Willoughby’s murder, encouraging or assisting the commission of her kidnap and encouraging or assisting the commission of her rape, according to a press release.

Essex Detective Chief Inspector Greg Wood described Plumb as “a dangerous and predatory individual who was intent on causing the most serious harm to his victim,” in a July 4 press conference.

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“He was not just obsessed with Holly Willoughby as he claimed. He carefully planned, over a number of years, to carry out a violent attack in which he plotted to kidnap her from her home, take her to a remote location and ultimately take her life,” Wood said.

“He carefully planned, over a number of years, to carry out a violent attack…”

— Greg Wood, Essex Police DCI

The obsession dated back to 2021, and Plumb plotted with others online to carry out his violent plan.

Plumb did “extensive research” to try and devise a plan in which he could kidnap Willoughby from her family home, police said in a press release. 

The defendant also made purchases to assist him with carrying out the crime, including metal cable ties, ropes and chloroform.

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During one of Plumb’s many discussions online, in October 2023, he did not realize that one of the users he was communicating his plans to was the Minnesota detective who eventually flagged him to U.K. officials.

Plumb had prior convictions relating to the false imprisonment and attempted kidnap of women, including two 16-year-old girls, Essex police said.

“Today, we’re extremely grateful to our law enforcement colleagues in America, who not only brought Gavin to our attention but helped gather the vital evidence that secured his conviction,” Wood added.

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During his eight-day trial, Plumb testified that his murder plot was all a “fantasy” and a “massively regrettable” mistake. He also confessed to spending 99.9% of his time online, according to The Guardian. 

Regardless, a Chelmsford crown court jury found Plumb guilty earlier this month after hearing evidence against him, including what the Owatonna officer helped compile.

Following his conviction, Essex police posted a video of Plumb’s initial arrest.

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“I’m not gonna lie, she’s a fantasy of mine,” Plumb can be heard saying in the video when police confront him about the allegations.

Willoughby, who has presented for TV shows including “This Morning” and “Dancing on Ice,” released a statement after Plumb’s conviction saying, in part, that she will “forever be grateful to the undercover police officer who understood the imminent threat, and to the Metropolitan and Essex police forces for their swift response.”

“As women, we should not be made to feel unsafe going about our daily lives and in our own homes.”

— Holly Willoughby

Chief Mundale said the Owatonna Police Department Detective Unit “uses online platforms to monitor criminal activity and chatter to gather intelligence.”

“These investigations have no geographic boundaries and generally land in other states and countries,” Mundale explained. “These covert investigations are conducted across various and changing social media platforms searching for individuals with a criminal mind and intent to traffic minor children or persons that are seeking to hire for rape or murder.”