Investigation Discovery HD (Pacific)

When someone stabs Trina Langenbrunner to death and leaves her on a road in Cloquet, Minn., her family, community, and law enforcement work together for over 12 years to find her killer.

Montie meets Shaynna on Halloween, but she turns out to be a horror show.

Sean Scott marries his high school sweetheart, Wendi Ellis, but things soon turn sour as Wendi racks up bizarre and destructive offenses; in the final conflict, Sean must choose between his family's survival and his sworn vow.

Recently divorced Brian Cargill thinks he's met the woman of his dreams; however, Kimberly Cargill is a master manipulator, and her abusive and violent nature tragically leads to murder.

Single mom, Wilda Gadd, finds a family-oriented single dad who seems like the perfect life partner, until he devolves into a dangerous monster; she's the only one who can bring him to justice.

A woman disapproves of her granddaughter's new boyfriend and plots to eliminate him; a man pays for his wife's expensive secret with his life; a woman takes matters into her own hands after her retired husband falls ill.

When some couples unite, they spark a terrible urge for destruction.

Ciera Harp snaps after realizing aspiring rapper Rahim Grant will never be hers; Linda Ricchio's possessive behavior wears thin with boyfriend Ron Ruse; grandmother Loretta Burroughs marries her high school sweetheart, Danny, then he disappears.

Women who seem sweet natured turn out to be killers.

When some couples unite, they spark a terrible urge for destruction.

Ciera Harp snaps after realizing aspiring rapper Rahim Grant will never be hers; Linda Ricchio's possessive behavior wears thin with boyfriend Ron Ruse; grandmother Loretta Burroughs marries her high school sweetheart, Danny, then he disappears.

Women who seem sweet natured turn out to be killers.

A woman disapproves of her granddaughter's new boyfriend and plots to eliminate him; a man pays for his wife's expensive secret with his life; a woman takes matters into her own hands after her retired husband falls ill.

Margaret Purk is just days away from having her first baby when she is found dead from an apparent suicide; 24 years later, new clues lead investigators to re-open the case.

In St. Petersburg, Fla., Cabretti Wheeler and his friend, Kyle Ellis, are killed; after the only eye-witness vanishes, it's up to Wheeler's mother, Lisa, to help police solve the case, even if it means risking her own life for justice.

Motivational speaker Jeffrey Locker, 52, is found stabbed to death in East Harlem, N.Y.; at first, detectives suspect Locker was in the wrong place at the wrong time, then they learn the truth is far more complex and shocking.

The body of 20-year-old student Sandra Bonaventure is discovered in a garbage bag on a sidewalk in New York City; the trail of clues lead to a cold-hearted killer who possesses an astonishing talent for deception.

Peter Theriault, 51, has never missed a day of work in nearly 30 years, then he fails to arrive for his shift at a car plant in Commerce City, Calif.; his family and friends immediately suspect that something is very wrong.

Carmen Quinones and Ruben Frederick are brutally stabbed to death in their East Harlem apartment next to $16,000 in cash.

In Tacoma, Wash., businessman Robert Henry is murdered by a masked gunman, and his wife, Paula, points the finger at Henry's former business associate, Larry Shandola.

Bob Peterson invites himself over to his co-workers Gene and Jaye-Jaye Thurnau's new home to give them a housewarming present; later, Jaye-Jaye leaves the guys alone to run an errand, during which time they vanish.

After Gayle Isleib is shot to death on April 30, 1996, police identify her coworker, Tyronne Montgomery, as her killer; they find love poems as well as evidence that Montgomery planned to kidnap Isleib and murder her husband.

When Andrea Farrington meets fellow employee Alex Kozak, she feels that romance could be on the horizon, then Farrington's hopeful feelings are replaced by suspicion and fear, leading to a final rejection that has fatal consequences.

William Cosden Jr. coerced his much younger sisters, Karen and Susan, into keeping secrets about what he did; now the girls are adults, and with one facing death, they reunite to try to repair the trauma keeping those secrets caused them.

Genie already knows Lee Cawthon is capable of horrible things when he forces her into a polygamous relationship; she plays along with his twisted demands, but doesn't realize that the consequences of letting him have his way might be worse.

When she wakes from her coma, Melanie puts the puzzle pieces together; she had worked so hard to make her relationship with Tracy work despite his lies and abuse; when she reflects on their past, she realizes he's been trying to kill her.

Betty hopes her sister's son, Chance, is a beacon of hope in their troubled lives, but Betty sees his dark side early on; he lacks empathy and becomes violent until he explodes in a fit of rage, harming the one person who cared for him most.

When Dreamer meets Teddy, she sees a broken young man and hopes her love will change him; he returns her love with fear, cruelty and control; after her father tries to help her escape his clutches, Teddy makes them pay a price.

When Ryan's mother marries Blaine Nelson, he hopes he'll gain a fun-loving stepdad; instead, he gets chaos, pain and fear, and while Blaine relishes tormenting Ryan, he can never imagine just how dark and sadistic his stepfather truly is.

Behind closed doors, India Mackey's relationship with her boyfriend is painful; one day after her 20th birthday, India learns what he is truly capable of.

A phone call disrupts a peaceful summer afternoon in Helendale, CA, instantly turning a woman's life upside down. Detectives chase shadows through surveillance footage, cryptic messages, and hidden ties as answers to a murder begin to surface.