Two distraught women call 911 when they discover their sister brutally murdered; soon, detectives uncover a stunning surprise and struggle to find a killer whose self-hatred drove him to commit the ultimate crime in a precedent-setting case.

A terrified neighbor calls 911 after witnessing a young mother being gunned down in her driveway; police work to uncover a complex conspiracy that ripped the loving mother from her three children, just to keep dark secrets hidden.

Police in two cities receive a series of bizarre 911 calls from a serial killer confessing his crimes; the man becomes known as the Weepy Voiced Killer due to his strange, whining voice.

A dying man calls 911 to say he's been shot in the heart and his son has been shot dead; after the shooter escapes into the night, the detectives must navigate a complex group of suspects to uncover a tangled web of rage and revenge.

Calling 911, a woman whispers that intruders broke into her home, bound her and her son and attacked her husband; police arrive to find the husband dead and the killers gone; investigators struggle to expose the twisted mastermind behind the crime.

With the help of a neighbor, an injured woman calls 911 saying an intruder broke into her boyfriend's home and shot them both; police respond to find the boyfriend executed; they must decipher strange evidence left behind to identify the killer.

Church parishioners call 911 when they find their priest stabbed to death, then police uncover an earlier 911 call made by the priest himself and track a missing cell phone to find his killer.

A man calls 911 screaming for help but is too terrified to give his address, and police scramble to find him; as detectives investigate, they uncover a shocking tale of torture and revenge that demonstrates the deadliness of unrequited love.

A man calls 911 to report he's on the telephone with his girlfriend who's in trouble; when police respond, the door is answered by the woman's two frightened sons, and she has been severely beaten.

A panicked woman calls 911 to say a stranger forced his way into her home and shot her boyfriend in front of their children; detectives untangle a twisted web of jealousy to find out who killed this young father and why.

A frantic woman calls 911 when she finds her husband shot to death; the investigation reveals allegations of harassment from the victim's ex-lover and eventually uncovers a complex trail of deceit, in a murder that was years in the making.

When a young woman is shot dead in front of her son, horrified witnesses call 911 and describe the shooter as a slender man who disappeared into nearby trees; though clues are scarce, investigators finally uncover the killer's shocking identity.

A woman calls 911 to say she's found her son unconscious in his home; when police arrive, they realize he's dead; the victim's hands are bound, and he's been strangled; at first, it seems like a burglary gone bad, but police soon discover otherwise.

A terrified woman tries to give police clues in a harrowing call, then police find her body in the river, and they discover a stomach-churning truth about a killer who's been a predator for years.

A man calls 911 claiming he found his ex-girlfriend dead, but his behavior on the call leads police to wonder if he could be involved; investigators gather evidence to convict a killer whose unchecked rage left a young son motherless.

After a doctor is shot at his ranch during a chaotic assault, investigators follow a trail of vehicles, surveillance footage and telephone records to discover a plan hatched by a band of brothers.

A frantic woman calls 911 saying an intruder just entered her home and shot her husband; when a local fire chief dies from his injuries, first responders work tirelessly to find out who killed one of their own.

A traumatized man calls 911 after seeing his friend shot and killed right before his eyes; with a surprisingly long list of suspects, investigators must sort through layers of lies, jealousy and mistrust to uncover the shooter.

A woman returns home to find her husband unconscious and bleeding on the floor of their horse barn; a 911 operator coaches her through CPR, but it's too late, and police later use the call itself to find clues to a plot to kill a beloved father.

Calling 911, a young father gasps that he has accidentally shot himself while working on a farm, then police hear a second shot on the line while racing to find him.

In a distressing 911 call, a woman reports someone is breaking into her home, then the dispatcher hears a scream and a gunshot; investigators soon connect the case to a previous home invasion and race to solve the crimes.

Viewers get a seat at the table when Louisiana detectives meet to discuss their most difficult, high-profile, and emotional murder cases from the 1990s through the 2000s. Hourlong episodes reveal the personal accounts of the now-retired cops, who ultimately cracked the cases while they worked the streets of New Orleans and its surrounding communities. Powerful interviews and stylized re-creations bring the stories to life, showcasing how dedicated these men and women were to solving the most heinous murders the Big Easy has ever seen.

This true-crime series revisits haunting murder investigations through the eyes of one person -- the heartbroken sister, the restless detective, the dogged reporter -- at the emotional and dramatic center of a case. Utterly unique, the single storyteller recounts an intimate experience, played out via stylized re-enactments, but his or her point of view and the story that is told may be more surprising than expected.

Rod Demery's destiny was sealed at the age of 3. That's when his mother was murdered, and Demery would come to realize that he wanted to protect people who couldn't protect themselves. He did so by serving for 14 years as a Shreveport, La., homicide detective, working on more than 250 cases and solving each of the 60-plus investigations on which he was lead detective. In "Murder Chose Me," Demery reflects on his stellar career, guiding viewers through first-person storytelling that weaves his uniquely tragic personal connection to the story of each homicide he solved.

"Who Killed Jane Doe?" presents a unique journey of discovery, loss, mystery and resolution. Featuring Investigation Discovery's distinctive stylized re-enactments, each hourlong episode weaves together two parallel stories: that of detectives who gather clues to identify a victim and the manner of death, and that of a family who knows very well who the victim is and is struggling to find her. The emotional tales honor the nameless and offer a final resting place to a missing loved one.

"Murder by Numbers" begins in a similar fashion to many true-crime series. After a body is found, an intense investigation commences, quickly turning the focus to a very likely subject. But just as the viewer eases into the case via cinematic re-enactments and through the eyes of detectives, a shocking discovery of a second body not only eliminates the original suspect, it redirects the investigation on a harrowing journey of pure criminal evil.

While most killers act alone, there's another type of murder that happens less frequently yet still produces horrific consequences. That's when people decide to kill as a group. This Investigation Discovery series details true-crime cases that involve victims who have been savagely murdered by their own friends. Stylized re-enactments featuring first-person accounts from law enforcement personnel and friends and family of the victims accompany each story.

"Accident, Suicide, or Murder" investigates the deaths that are considered just a little bit too mysterious. This hourlong series takes viewers along on an exploration of unbelievable true stories. Each episode retraces the original investigations from the start to the finish. Investigators lead viewers through all of the twists, turns and surprises that crop up as they dissect the red flags, show evidence, and point out the strange behavior that puts everything into question.

From the moment a homicide is reported, a file is assembled to document every facet of the investigation -- crime scene photos, notes and observations, forensic reports, witness interviews, suspect profiles -- and continues to grow with new information until an arrest is made and conviction attained. Investigation Discovery opens these "murder books" to tell haunting tales buried within the pages. Hourlong episodes take viewers back in time with details of decades-old cold cases using actual archival footage, crime-scene evidence and first-person interviews with lead investigators, unraveling the mystery and uncovering what broke the cases open.

Crimes and mysteries are investigated.

"Dateline," NBC's long-running newsmagazine series, brings its cutting-edge, heavy-hitting journalism style to Investigation Discovery, bringing viewers harrowing crime stories and tackling topics of broader importance to society. Hosted by either Lester Holt or Keith Morrison, the repackaged episodes go behind the headlines to introduce the detectives, the suspects, the victims, and the families involved in a devastating criminal investigation. Emotions play out in a courtroom, where dark secrets are laid bare until a verdict is revealed.