Mistress who turned in treacherous FBI spy Charles McGonigal is mysteriously found DEAD: Her haunting final texts revealed… as grieving dad insists she ‘would never’ take her own life

The mistress who helped bring down jailed FBI spy Charles McGonigal has died suddenly at her home in south Florida, the Daily Mail can reveal.

Allison Guerriero, 52, passed away hours after sharing a flurry of 75 posts on X on Thursday, including a video of herself walking in the street demanding a spotlight on other Feds and another where she declared: ‘I hate the FBI.’

They were part of her unrelenting years-long campaign often conducted on social media against married McGonigal, 58, and her personal war against other senior figures in the agency.

Guerriero, a close friend of former New York City mayor and Trump stalwart Rudy Giuliani, died sometime in the evening of August 27, according to her devastated 80-year-old father Bill.

Her 18-month affair with the treacherous former head of the FBI counter intelligence in New York helped blow the lid on McGonigal’s crimes, which included secretly working for Russian oligarch Oleg Deripaska.

He is serving six years and six months in federal prison, but Guerriero always believed he should have received a harsher sentence, telling the Daily Mail in 2024: ‘He’s a traitor.’

On the day of her death, she posted a selfie video of her strolling in her relatively new hometown of Boynton Beach, Florida, saying: ‘Hey, good morning everybody. Friends and enemies… of course I’m in the middle of all my PTSD from 9/11 but I’m actually breathing a huge sigh of relief…

‘Here’s the problem with Charles McGonigal. You know his name, but you never did before that. You knew Jim Comey’s name. You knew Chris Wray’s name.. all the names that you already know, you know. Why don’t you start looking for the names that you do not know?’

Her father, who lives in Guerriero’s former hometown of Florham Park, New Jersey, told the Daily Mail he has not yet been told the cause of death or the circumstances.

‘We really don’t know yet. We’re waiting to get access to the autopsy report. I believe they’re going to issue a death certificate within the next day so we can get her home and have her put to rest,’ he said.

‘It could have been an accident. She could have slipped. It could have been anything. We’re waiting for the death certificate so we know what happened.’

A Boynton Beach police spokesperson told the Daily Mail that ‘there do not appear to be any signs of foul play at this time,’ but that the investigation is ongoing.

Police responded at 8.03pm Thursday to her apartment at 1499 S. Federal Highway in Boynton Beach. Police are awaiting info from the medical examiner’s office.

Former security consultant Guerriero was also close to Roger Stone, the Florida-based conservative lobbyist and ally of President Trump.

‘I heard from her by text on the day she passed away and she seemed in excellent spirits,’ he told the Daily Mail. ‘They were work related. She was helping with some research.

‘Allison was a brilliant researcher and writer with an excellent knowledge of both law enforcement and our intelligence capabilities and wide network of contacts. She was widely respected in that world.’

Guerriero, who moved to Florida three years ago, was a cancer survivor and also battled severe and permanent injuries following a horrific fire.

‘She was a devout Roman Catholic. She was always trying to get me to go to Latin mass with her. She was an optimist. She had boundless energy, given her various health problems,’ Stone added.

Discounting suicide, he continued: ‘There’s no doubt that she would never take her own life. She was too devout a Roman Catholic. She would never do that. 

‘She overcame enormous adversity in her life. I’m going to miss her tremendously.

‘She was obviously still very unhappy with the fact that McGonigal should have been charged with treason but instead was only charged with taking bribes. She was extremely aggravated.’

While the cause of death is unknown publicly, other sources have hinted at possible darker reasons behind it.

One told the Daily Mail: ‘She was getting threatened a lot by people online for her views. She certainly had enemies.’

Guerriero’s father countered that theory, saying: ‘She showed no concern that there was anyone trying to harm her or anything like that. I really don’t think there was anything suspicious, not from what I know about this.

‘I’m skeptical that there may be anything nefarious here. Believe me, I’m her father and if there were, I’d be adamant about it.

‘Since she moved to Florida she’s been the happiest I’ve ever seen her. She was treating herself very well. She was walking every day, exercising and eating right. She enjoyed getting up at dawn and walking on to the beach.’

Boynton Beach Police Department said ‘there do not appear to be any signs of foul play at this time’, but an investigation is ongoing.

Journalist and political consultant Ken Kurson, pardoned by President Trump over a cyberstalking conviction, said of Guerriero in a Facebook post: ‘I never met anyone like her. I can use adjectives to describe her – loyal, chaotic, irreplaceable, occasionally even brilliant.

‘But those words fail to capture someone who boundlessly loved her family and hundreds of friends, supported them so intensely that their critics became Allison’s enemies, their struggles and hopes and aspirations her own… I am bereft.’

Guerriero was a former vice president of US operations for Israeli security firm Mifram while working in New York. 

She first met McGonigal in spring 2017 as a volunteer for the Federal Enforcement Homeland Security Foundation charity.

The then $200,000-a-year Fed wooed her over dinner, claiming he was going through a divorce from wife Pamela who he called ‘a nag’ who never agreed to sex.

His family home was in Chevy Chase, Maryland but he lived in a sublet apartment in Park Slope, Brooklyn following his 2016 New York appointment by then-FBI director Comey.

In the three years before her death, Guerriero was exclusively interviewed several times by the Daily Mail, spilling on the couple’s sex life and McGonigal’s treachery.

She said they first had sex in a black Ford Explorer government SUV after she showed him where she went to high school in Florham Park.

Shortly afterward, Guerriero moved into the Park Slope apartment believing the spook had separated from Pamela and was getting a divorce.

‘He did say she was an excellent mother but the marriage was dead and they were both moving on.

The former mistress added: ‘I don’t know if he actually was separated from his wife. I wish I knew. I don’t know what to confess. 

‘My priest is so sick of hearing me confess adultery that I don’t know if I did commit adultery.’

While they were together, McGonigal flaunted his relationship with Guerriero, taking her into the FBI’s main office in Manhattan and up to what she calls the ‘Kings of New York’ floor – introducing her as his ‘girlfriend’. 

He cleverly masked signs of his overall treachery, passing off any outward clues as part of his role. 

He took a trip to Albania during their relationship in 2017 and at one point asked Guerriero to accompany him to meet sanctioned metals magnate Deripaska, a crony of despot President Putin.

In early October, the couple were due to enjoy a meal for Guerriero’s birthday. But the celebration was abruptly canceled because the then-FBI director Christopher Wray came into town and McGonigal had to attend meetings.

‘So we went out either the fifth, sixth or seventh of October,’ said the former mistress. According to court papers, on October 5 McGonigal received $80,000 from his former Albanian intelligence official associate in a car parked outside a New York restaurant.

Guerriero cannot recall anything that happened the night they were out that would point to the handover. But she does now wonder if the celebration was a smokescreen.

Weeks later she made a startling discovery in their apartment. A bag containing what she now knows was $80,000 in $100 bills, neatly rolled.

‘My mind went to them being what we call flash rolls, money you would give an undercover informant or an undercover agent for them to continue operating in the field,’ she said. ‘They were in a black plastic bag with gold writing, the sort you’d get from a liquor store. It wasn’t particularly hidden, it was just by the main door.’

Challenged, McGonigal claimed he had won the money betting on a baseball game. Guerriero listened patiently, but her suspicion antenna was beginning to twitch.

However, it was McGonigal’s confession that he was not divorcing his wife that led to their breakup on Christmas Eve, 2018 – three months after he retired from the FBI and later became an $850,000-a-year head of security for a bank.

‘He said he was staying married, that he and I were breaking up,’ said Guerriero. ‘I said, what the hell were we doing for the last 18 months?’

McGonigal’s decision to quit the relationship may have heralded his eventual downfall. 

Guerriero tipped off people she knew at the FBI about her suspicions in 2019 after reflecting on events.

Her accusations appeared to have fallen on deaf ears, although the wheels of justice obviously did begin to turn on McGonigal and he was arrested in January 2023. At the time, he and Pamela were living in Manhattan.

‘After Charlie and I had broken up, I had spent a series of weeks and months rolling everything over in my head,’ she said.

‘And it had occurred to me, this guy’s a traitor. He was accepting bribes to peddle influence. He was accepting bribes to work with Oleg Deripaska, who he invited me to meet in Vienna when we were still dating.

‘And every time I tried to talk to the FBI about it, they didn’t want to listen. I told his former boss, I told other people within their senior executive service and nobody did anything. 

‘The FBI and the United States Justice Department did not want to hear that their superstar was compromised.’