I’m driving a rental SUV on a stretch of mountainous road somewhere near Alpine, California. Next to me is Callahan Walsh, co-star the new Investigation Discovery series In Pursuit With John Walsh hosted by his dad, and we’re talking details of an open serial child molester case. We are on the trail of a fugitive name Rick McLean, a real wolf in sheep’s clothing.

“I think there’s a special place in hell for anyone who intentionally harms a child,” Cal says. “And that hell looks like the inside of a jail cell.” Cal has reason to be so certain of this, as his older brother Adam was brutally abused and murdered. Though that tragedy occurred some years before Cal’s was born, growing up in a family dedicated to finding that killer has made him the man he is today.

Everyone knows about the F.B.I.’s Ten Most Wanted fugitives, but we don’t really stop to think about who these people are. John Walsh’s crusade to hunt down thugs from this list has been an ongoing mission since the loss of his 6-year-old son Adam in 1981. His top 10-list expanded into the thousands of criminals on the run who still need to be brought to justice. Walsh’s tireless pursuit of justice has earned him a first-name-basis relationship with law enforcement agencies around the world, building a network of contacts that has been supercharged by his TV shows America’s Most Wanted and The Hunt with John Walsh. And boy, has he put that network to good use: In the 25-plus years those TV shows have run, viewers’ tips have led to the arrest of over 1,200 fugitives and the recovery of over 60 missing children.

Cal Walsh, seated, and Brian DeCubellis while shooting “In Pursuit With John Walsh.”

The loss of their first son also compelled Walsh and his wife Reve to found the National Center for Missing and Exploited Children, a non-profit organization whose mission is to help find missing children, reduce child sexual exploitation, and prevent child victimization, by working closely with law enforcement, and families. This is where Callahan works when he’s not appearing as a correspondent on In Pursuit.

John Walsh has come out of retirement for his new show, In Pursuit With John Walsh (Wednesday’s 10pm EST on Investigation Discovery), to make another run at catching bad guys. And he’s brought his son Callahan on board to go on the ground, in cities all across the America, for a close look at the stories of these perpetrators and their victims. I am In Pursuit’s verité director and supervising producer.

As a director and producer working for Zero Point Zero Production, I’ve worked on many TV shows where the mark of success is how well the story is told. Working on In Pursuit, the stakes feel radically different. I’ve had the unique experience of flying from city to city with Cal, filming scenes of him meeting with victims’ families and loved ones, visiting crime scenes, and digging in with the police detectives and Federal Marshals working these cases. I saw first-hand the expressions on the faces of parents coping with the unthinkable loss of their child, sister, or friend to murder at the hands of a spouse, fiancé, boyfriend or acquaintance. Here, stories well-told can actually lead to the apprehension of these wanted outlaws — and to some degree of peace for those so adversely affected by their crimes.

Here in Alpine, we’re investigating the case of Rick McLean, wanted for molesting over 100 prepubescent girls. He was an active leader in the Jehovah’s Witnesses community, often hosting family outings, camping trips and kids’ sleep-overs. He was the most amiable, beloved member of a tight-knit chapter. As one young girl came forward with an account of abuse, word spread and dozens more spoke up. Using information from local police detectives and Federal Marshals, including a bizarre treasure map that McLean left his family when he disappeared that was to point to some cash that he left for them. By the time the code was cracked as to the location of the stash, detectives dug up an empty container. We’re filming to hear from the key players in this case. The hope is that maybe some detail of their accounts will spark a viewer to remember something useful that will reveal Rick’s current location. Cal and I are doing this case after case, in city after city.

In Atlanta we spent the day in the home of a mother whose daughter was killed by her ex-boyfriend, a wannabe rapper named Maurice Nesbit who went by the name Mega Ruckus. Nesbit was convicted of the murder, but cut his ankle monitor and slipped town while the jury was delivering the guilty verdict. In Boulder, Colorado we dove in to a well-known cold case, the search for Thayne Smika, a man wanted for killing his roommate, 22-year-old Sid Welles, back in 1983, rather than paying him rent. Welles was dating Robert Redford’s daughter Shauna at the time, and over 35 years later, the town is still haunted by the event — as well as the unsolved Jon Benet Ramsey case.

In St. Louis, Cal and I were welcomed into the home of a woman Patricia Hamilton who raised her sister’s twin boys, only to see them both shot by a family friend named Derek Dean. Only one of the twins, Edwin Cohee survived. To hear him recount the moments leading up to the event, and to walk the crime scene with the lead detective and Federal Marshal describing how Dean pulled a gun at a 4th of July party and took aim at his friends who he had just an hour before praised for getting out of the old neighborhood, left us speechless.

Again and again we dropped into lives damaged forever. My wife asked if I saw any common threads between the cases. My reply was to note was that regardless of socioeconomic or ethnic background, the wreckage of abuse and murder by someone you know is exactly the same. It is absolute.

Traveling around the country with Cal, I’m struck by how knowledgeable he is on such a wide variety of topics. I’m also aware of how his sense of direction is sharper than average, as is his awareness of what’s going on around him. It’s as if he’s constantly tracking, investigating and collecting information for his own mental database.

“Knowledge is power” is more mission than mantra for Cal, and his drive to find these fugitives is palpable. Many of the victims’ loved ones we met told us there can never be “closure.” Yet every single one of them said bringing the perpetrators to justice will bring the closest feeling to closure possible.

In this premier season of In Pursuit With John Walsh, Cal is on the cases of these fugitives wanted for the following:

Maurice “Mega Rukus” Nesbitt – convicted of murdering his ex-girlfriend (2014)

Frederick “Rick” McLean – wanted for molestation of over 100 children 1980s – 2005)

Brian Keith Freeman – wanted for murder of his ex-fiance (2017)

Harold “Butch” Knight – wanted for murdering his wife (2015)

Derek “Man” Dean – wanted for murder of his friend (2014)

Ricardo Villaneuva Cordova – wanted for murder of his neighbor (2013)

Tomas Gonzalez – wanted for murder of his step daughter (2008)

Rudy Fernandez – wanted for murder of his girlfriend (2001)

Jesus Salazar – wanted for murder of friend (1999)

Christopher Deininger – wanted for molestation of toddlers (1997 – 2000)

Gloria Schulze – convicted of vehicular homicide (1994)

Thayne Smika – wanted for murdering his roommate (1983)

During the airing of the first episode a viewer in Mexico recognized the face of fugitive Luis Arias, wanted for stabbing the mother of his three children to death right in front of them. He’s now in custody because that viewer picked up the phone and called.

And that’s a great feeling. It fuels me as I meet with so many folks touched by tragedy, and it adds resonance to something Cal told me on one of our shoots, a phrase he learned from his Dad, “Justice delayed is not justice denied.”

Brian DeCubellis is an award-winning director/producer working in TV and film whose credits include the feature film Manhattan Night.