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.

John Walsh spotlights freshman Jihad Ramadan, who allegedly introduces a knife to a fistfight that claims a star college student's life. Later, Callahan Walsh looks for Thayne Smika, who, police believe, shoots his roommate in cold blood over back rent.

An ex-Marine seems like a knight in shining armor to a single mom, but as John Walsh reveals, she was far from safe. Then, Callahan Walsh discovers how rapper Maurice Nesbitt's abuse of his girlfriend eventually turns deadly.

Salvador Vaca Garcia makes a tearful appearance on local news after his girlfriend disappears. Then, Callahan Walsh looks at Brian Keith Freeman who allegedly attacked his fiancé when their engagement fell apart.

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 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 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 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 vet who is accused of waging a lethal war against his young wife. Later, Callahan looks at Rudy Fernandez, whose teen romance with his high school sweetheart is believed to have turned deadly.

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.

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.

The case of youthful con man Edgardo Perez, who allegedly preyed on older men until it turned deadly; Callahan Walsh travels to Boulder where teenage babysitter Chris Deininger confessed to abusing 29 kids in his care before fleeing.