John Walsh profiles triple homicide suspect Mike Bullinger who led a double life; Callahan Walsh looks at the case of Tomas Magallon Gonzalez, who allegedly sexually abused his stepdaughter for years before taking her life.

John Walsh investigates how Eric Jones, the son of a preacher, allegedly turned to murder; Callahan Walsh tries to make sense of how a dispute over a dog could provoke Ricardo Villanueva Cordova to reportedly commit murder in broad daylight.

John Walsh profiles Juan Lazaro Abrego who is believed to have murdered his ex-girlfriend, a beloved schoolteacher; Callahan Walsh investigates Derek Dean, a St. Louis man accused of shooting identical twins, killing one and wounding the other.

John works with investigators to bring Frank Contreras into custody after he commits a terrible crime witnessed by a child; Cal takes on a heartbreaking case where authorities desperately need the public's help to identify a vicious criminal.

When an unthinkably violent criminal flees before his trial, John Walsh joins local authorities on the chase for Michael Waguespack; Cal uncovers hidden and painful truths in a Christmas Eve tragedy that sent police hunting for Miguel Angel Martinez.

John Walsh investigates Alicia Osibin who is wanted in connection with the shooting death of her elderly mother; Callahan Walsh speaks to Andrea, an alleged victim of Frederick McLean's abuse, who is still desperate for McLean's capture.

Salvador Vaca Garcia makes a tearful appearance on local news after his girlfriend disappears; Callahan Walsh looks at Brian Keith Freeman who allegedly slit his fiancé's throat when their engagement fell apart.

Luis Frias makes John Walsh's most-wanted list after allegedly stabbing his common-law wife to death in front of their children; Callahan Walsh explores the case of Harold Butch Knight, who left a trail of clues after confessing to killing his wife.

A family feud escalates to violence and John joins police in pursuit of one of the FBI's Top 10 Most Wanted fugitives, Eugene Palmer; Cal helps authorities track down Tamera Williams.

John joins the hunt for prominent community members Torin and Rena Smith, who absconded from justice after being accused of shocking crimes; Cal pulls back the curtain on Carnell Spencer Lee Jr., a vicious criminal with a dark and menacing past.

When a cunning sexual predator is found hiding in plain sight, John helps police in the pursuit of dangerous James Meece; after a vicious home invasion, Cal goes into the field to help police find the savage James Watts.

When an insidious sexual predator is discovered hiding in plain sight, John helps police in the pursuit of James Meece; after a brutal home invasion, Cal goes into the field to help police track down James Watts.

John joins police on a strange and twisting missing persons case that turns fatal, sending investigators on the trail of Alejandro Castillo. And Cal takes on the case of Leticia Smith, a woman on the run from a terrible crime with nothing to lose.

After a vulnerable elderly man is brutalized in his rural home, John joins a manhunt for Derek Whisenand; then newlywed bliss turns into a vicious crime, so Cal goes on the trail of fugitive Arnoldo Jimenez.

John Walsh investigates the accusation that Lamont Stephenson strangled his fiancé and her dog; Callahan Walsh explores police claims that Gloria Schulze is a drunk driver who repeatedly cheats the legal system.

John Walsh spotlights Jihad Ramadan who allegedly stabbed a fellow university student to death; Callahan Walsh looks for Thayne Smika who reportedly shot his roommate in cold blood over back rent.

John Walsh tracks the story of convicted killer Glen Stark Chambers, who beat his young girlfriend to death and then escaped prison twice; Callahan Walsh investigates a murder suspect who eludes capture for 20 years.

John Walsh profiles John Blauvelt, a troubled U.S. Army veteran who is accused of waging war against his young wife; Callahan Walsh looks at Rudy Fernandez, whose romance with his high school sweetheart is believed to have turned deadly.

John Walsh reveals that a single mother is far from safe with ex-Marine Raymond R.J. McLeod who initially seemed like a knight in shining armor; Callahan Walsh discovers how rapper Maurice Nesbitt's constant abuse of his girlfriend turns deadly.

When a double shooting leaves one woman dead and another clinging to life, John joins police on the trail of fugitive Lenell Kirby; Callahan takes on the murder of a dear Walsh family friend, Lindsay Harris.

A costly mistake allows criminal Lester Eubanks to escape justice, so John steps in to help investigators; Cal looks into the case of William Stanson, a so-called loving father who turned out to be a sexual predator.

Victims' rights activist John Walsh returns to weekly TV as host of a documentary-style investigation series. Walsh details stories of ongoing cases involving fugitives, with the intent of expanding searches outside the United States. Interviews with victims, loved ones and law enforcement accompany new leads in each hourlong episode, giving the public information to facilitate the capture of suspects. Walsh, a spokesman for the National Center for Missing & Exploited Children, hosted the series "America's Most Wanted" for 25 years, helping apprehend more than 1,200 criminals.

In this eight-episode series, viewers hear directly from detectives who investigated cases that haunt them to this day. These true-crime stories -- from mysterious vanishings to twisted family murders -- are the "unforgettable cases that disrupt law and order, and keep authorities up at night," says Investigation Discovery.

Like a pane of glass cracking in all directions before shattering, the impact of a single crime can create ripple effects that forever alter multiple lives. This Investigation Discovery series unravels actual homicide cases to explore how the past continues to haunt the present for those involved -- loved ones, witnesses, and law enforcement. Each episode is structured around three distinct perspectives of the same crime, and as viewers learn different details by way of first-person interviews and stylized re-enactments, stories, which at first seem random, slowly start to intertwine.

Crime author and investigator Jax Miller and former police investigator Sarah Cailean tackle a mystery that has stumped authorities for nearly two decades -- the confounding cold case of Lauria Bible and Ashley Freeman, two Oklahoma teenagers who disappeared in December 1999 after the Freeman family trailer was burned to the ground. In the four-part documentary series, the investigators delve into the many strange theories of the case and unravel a much larger story of unsolved murder, allegations of cover-up and corruption, and a truth that proves even more incredible.

Here today, gone tomorrow. Thousands of people go missing in the United States each year, leaving behind only a mystery without any clues. Their stories are told in "Disappeared" through the voices of family, friends and investigators trying to solve the case, with each hourlong episode recounting the final stages that led to a person's disappearance. Interviews with experts including psychologists and forensic specialists provide new insights into what may have happened -- whether foul play was involved or the subject simply ran away.

Serious crimes are committed for a variety of reasons, and emotional triggers like passion, betrayal and rage often play huge roles. In this immersive, investigative series, Emmy-winning journalist Tony Harris relies on his reporting instincts to reveal the deeper stories behind crimes that shook communities. Each act underscores a world -- a small town, a hidden subculture, a criminal network -- behind and beyond the violence. While visiting various crime scenes, Harris hears personal accounts from victims, loved ones, and even culprits themselves, peeling back the layers to showcase often nefarious players and foreboding places at the center of the violent acts.

"Murder for Hire" gives an exclusive look into the dark world of contract killings, showcasing some of the most fascinating murder for hire cases ever caught on tape. In an alarming trend, investigators are seeing a sharp increase in hired hits across the country, and those attempting shockingly include: housewives, wealthy bankers, military officers and even grandmothers. From scorned lovers to jealous relatives, the show explores in rare, never-before-seen footage, how a seemingly good relationship can go wrong and the emotions surrounding the reveal when an intended victim discovers a hit has been taken on their life. Each standalone episode features a different case of undercover agents immersing viewers into the real-life sting and investigation as they attempt to catch the perpetrator and ultimately prevent a murder.

Since May 2014, six women in Chillicothe, Ohio, have gone missing or been found dead, leading the local community to fear a serial killer is responsible. Granted unprecedented access, Investigation Discovery teams with law enforcement, victims' loved ones, and the town's residents to document the investigation as it unfolds in an effort to help solve the open cases. Six hourlong episodes detail the circumstances, facts and evidence surrounding each disappearance. While the victims are believed to have known each other in some way, three of the women have been found dead in or near bodies of water, one was found shot to death, and two remain missing.

Secrets are never safe from seeing the light of day, even ones that are housed with skeletons and buried six feet under. Those, especially, are of interest to law enforcement personnel, who unearth long-thought gone secrets that eventually help unravel murder mysteries. The details are described in hourlong episodes of "Grave Secrets," with re-enactments providing the meat and potatoes of each true-crime story, and interviews with victims' family, friends, and investigators adding context.