Rob McLeod was flicking through a local newspaper in June 2006 when an article caught his eye.

A father had put up a billboard reading ‘Jennifer, where are you?’ outside Shotgun Willie’s strip club in Glendale, Colorado, seeking information about his daughter Jennifer Marcum who had been missing for the past three years.

It was a story uncomfortably familiar to McLeod.

It had been around three years since his own daughter Kaysi McLeod suddenly disappeared, never to be seen again.

But as McLeod read on, he realized there was something other than a father’s pain that connected their stories: the name of the last person to see their missing daughters alive.

‘It was just a throwaway sentence at the end of the story,’ McLeod told the Daily Mail. ‘And that was what set everything off.’

The article described a man named Scott Kimball who claimed he last saw Jennifer leaving his apartment to head to the airport in February 2003. Her car was found abandoned soon after.

Kimball was the husband of Kaysi's mother Lori McLeod and claimed to be an FBI agent.

In August 2003, he had claimed 19-year-old Kaysi ran away from the home she shared with him and Lori. Lori and Kimball had married later that month.

McLeod already had ‘an inkling’ something didn’t add up about Kimball.

Now, that inkling ballooned into the unthinkable.

He picked up the phone and called the local paper which connected him to Jennifer’s dad Bob Marcum.

The two dads quickly joined forces and, within weeks, they were marching into Denver’s FBI field office together demanding that Kimball be investigated in connection to their daughters’ disappearances.

‘We turned up first thing in the morning and told the FBI “you can either be the hero or the zero.” They could blow us off, and say these were just kids in trouble or they could take us seriously,’ McLeod said.

Little did the two fathers know that they had finally exposed a dangerous serial killer known as Hannibal - a master manipulator who had not only been under the nose of the FBI the whole time but had actually been enabled by the bureau to carry out his sick crimes.

Though not an FBI agent, Kimball was a confidential FBI informant.

Soon, he would be linked to a trail of missing people and confess to up to 50 murders in a case that cast a huge stain on the FBI.

What emerged was a chilling pattern where the informant fed the bureau false intel, negotiated his release from prison, lured in victims and got away with murder - all the while being paid by the federal government for it.

While on the FBI’s payroll, he claimed the lives of at least four victims and discarded their remains in remote locations across the Mountain states.

‘It wasn't until both dads teamed up and came into our office that my supervisor recognized Kimball’s ties to the cases were more than just coincidences,’ FBI Special Agent Jonathan Grusing, who led the investigation into Kimball, told the Daily Mail.

‘My boss came to me and said: ‘We’ve got a big problem.’ That's the only time the FBI ever cleared my workload.’

By this time, Kimball was already back behind bars on check fraud charges after leading police on a high speed, televised car chase. And so Grusing started listening in to his prison calls.

‘It quickly became clear that he could pull people under his spell to get them to do what he wanted,’ Grusing said. ‘He would play one person off against another person and isolate each person. He was extremely manipulative.’

Grusing soon realized the convicted conman and fraudster’s manipulation had infiltrated the FBI going back years.

It was 2001 when Kimball first began working as an FBI informant while in prison in Alaska for check fraud. He then worked as an informant for the Seattle and Denver field offices and was credited with stopping alleged hits on a prosecutor and a judge.

‘Scott controlled the narrative the whole time,’ Grusing said.

‘It was almost like the smarter you were, the more he could take advantage of you. He would give 70 percent truth, 30 percent deception. And if you didn't run that to ground, you would not find out the 30 percent deception.

‘He never graduated high school, but he could read people like no one I have ever seen.’

While in prison, Kimball would share intel with the FBI about alleged murder plots and negotiate his release to supposedly help foil them.

Meanwhile he also played his fellow inmates, leading them to believe he was helping them such as by making their charges, or people, disappear.

‘Scott used double talk. He would tell the FBI one thing and his cellmate something else,’ Grusing said.

He created codewords that the inmates and the FBI believed had different meanings.

For example, ‘the fish is fat’ meant ‘we’ll get your case overturned’ to an inmate. To the FBI, it meant someone was ‘going to have that person killed,’ Grusing said.

‘The cellmate would think that Scott was his savior. The FBI thought he was their savior. The whole time he was framing the cellmate and on top of that once he got out, the cellmate’s girlfriend would disappear.’

In December 2002, Kimball was in prison in Colorado, sharing a cell with Jennifer’s boyfriend Steve Ennis.

Conning the FBI into believing that Jennifer was involved in a murder-for-hire plot, Kimball was released from prison and paid to earn Jennifer’s trust and obtain information about the alleged plot.

In reality, the FBI had just freed the man who planned to kill Jennifer.

Less than two months on from his release that was exactly what he did.

Seven months later, Kaysi disappeared.

McLeod remembers Kaysi as ‘a very outgoing, fun kid.’ ‘As a young child she was very innocent. But after high school she had on and off trouble with drugs.’

By August 2003, the 19-year-old finally seemed to have put those troubles behind her. She had a steady job and was living with her mom and her mom’s then-boyfriend Kimball.

Then, Kimball claimed he found drugs in the house and that Kaysi had run away.

At first, McLeod said he and Lori were frustrated with their daughter.

‘I was more angry than concerned. I wanted her home, but she had been in trouble and ran away before so I was not too worried,’ he said. ‘We just thought she was off partying or getting in trouble on drugs.’

When days turned to weeks, months and years, their concerns grew.

‘We were getting more concerned, but we didn't think something terrible had happened. I was more worried about her being on drugs or having no food.’

But his suspicions mounted when Lori later revealed something: Kimball had also gone missing the same weekend that Kaysi disappeared.

While investigating Jennifer and Kaysi’s disappearances, Grusing discovered that Kimball was connected to the disappearance of another woman, LeAnn Emry, in January 2003.

In the 10 days before Emry disappeared, she traveled across the country writing bad checks. In her last messages to a cousin, she revealed fears for her safety and said ‘Hannibal’ - the former prison cellmate of her boyfriend Steven Holley - was protecting her. Her car was found abandoned in Moab, Utah, two weeks after she was last seen alive.

Then, a fourth victim - Kimball’s Uncle Terry - fell on Grusing’s radar. Uncle Terry disappeared in 2004 when Kimball claimed he had won the lottery and moved to Mexico with an exotic dancer.

Around six months into his investigation - and with four victims now tied to Kimball - Grusing sat down with the man he now suspected was a serial killer.

The special agent admits Kimball - a man who topped the scales on the FBI’s profiling for narcissism, psychopathy, sadism and Machiavellian - tried to manipulate him too.

‘It was quite the ride,’ he said. ‘I tried to speak to him as a father, saying to him: ‘How would you feel as a father if your kids were missing?’ He gave a flat response: ‘Why do I care what other dads think?’’

The case was complicated by the fact that Kimball was familiar with the FBI’s inner workings.

‘He knew how we worked. But on the plus side, he could not stop talking and would give away little hints and clues, even if he didn't mean to.’

But Kimball refused to confess or reveal where his victims were.

Then Grusing unearthed a receipt placing Kimball near Routt National Forest on the weekend Kaysi disappeared.

A human skull had been found in the forest. DNA testing proved it belonged to Kaysi.

In a disturbing twist, it emerged Kimball had taken Kaysi’s mother to the same spot where he dumped her daughter’s remains for their honeymoon just weeks after murdering and discarding her there.

‘That was so bizarre,’ McLeod said.

But he was relieved that Kaysi had finally been found.

‘When she went missing, I wanted more than anything to find my kid. Then the day they said she's not coming home but that they didn’t know where was, I was distraught,’ Mcleod said.

‘I knew she wasn’t coming home alive but I still wanted her home. I didn't care if it was only her pinky finger. The idea that she was dumped and alone and cold somewhere… So when her remains were found, I was very relieved.’

The discovery of Kaysi’s remains led to Kimball taking a plea deal in 2009, pleading guilty to second-degree murder of the four victims, avoiding first-degree charges in exchange for leading investigators to the remains of the other victims. He was already serving a 48-year sentence after being convicted in 2008 on fraud crimes.

LeAnn’s remains were found in Utah’s Book Cliffs and Uncle Terry’s near Vail, Colorado.

However, when Kimball failed to lead investigators to Jennifer, prosecutors renegotiated a harsher 70-year sentence.

In 2020, Kimball received another four years over a botched 2017 plot to escape prison and commit another murder.

Grusing continued to search for Jennifer and seek information from Kimball about her whereabouts up until his retirement from the bureau in 2021.

‘I probably spoke with him 50 times. He sent us on a lot of wild goose chases through different canyons. He sent us maps he had drawn, and told his attorneys about new places to search but we never found her,’ he said.

Kimball has continued to tell tales since his arrest.

In a prison interview to ABC’s 20/20, he claimed he was only a ‘mechanism’ in the murders of the three women and had accomplices.

To his attorneys, he claimed he murdered up to 50 victims.

Grusing said the accomplice story is just another lie from the master manipulator trying to again control the narrative.

But he ‘absolutely’ believes there are other victims still out there. ‘He told me personally he killed 21 and gave me a puzzle to solve to send me down a big rabbit hole.’

It’s a case that embarrassed the bureau and led to questions around how Kimball managed to play, manipulate and fool the FBI time and again.

‘We are human too,’ Grusing said. ‘We're no different than all the other people out there who were manipulated by him.’

The Daily Mail has contacted the FBI for comment. 

The case did lead to changes in processes for handling informants including tighter vetting and a requirement that two agents are always present at meetups.

But for McLeod and the other fathers and family members, these changes come too late.

Despite this, McLeod said it would be too easy to blame the FBI for its part in freeing Kimball to kill.

‘The minute I start assigning fault, if I say the FBI's 30 percent at fault, this person 20 percent, I'll end up with Scott being only 10 percent responsible,’ he said.

‘And that’s not right. Scott is 100 percent responsible.’

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