All Seasons

Season 1

Season 2

  • S02E01 In Harm’s Way

    • November 3, 2012
    • Investigation Discovery

    A woman goes out on a date and never returns home in the premiere of this documentary series about unsolved murder cases.

  • S02E02 Web of Lies

    • November 10, 2012
    • Investigation Discovery

    Employees at a security company receive a puzzling call from their boss; they learn that he has been shot and died.

  • S02E03 Relative Suspect

    • November 17, 2012
    • Investigation Discovery

    In 1974, Barbara Lloyd is stabbed to death in her Buffalo, NY home while her children are sound asleep. Police immediately question, how could they have slept through such a brutal murder? Could it be that her killer is someone they knew and loved?

  • S02E04 The Body in the Bay

    • November 24, 2012
    • Investigation Discovery

    A woman's body is found in the Chesapeake Bay, and it takes investigators four years to identify a suspect.

  • S02E05 Queen of Hearts

    • December 1, 2012
    • Investigation Discovery

    Bill Hassler returns home to find his high school sweetheart, Susan Schwarz, naked and shot three times.

  • S02E06 Not Again

    • December 8, 2012
    • Investigation Discovery

    When Carla Larson leaves work to grab lunch, she never returns. The all-American wife and mother is discovered naked and strangled to death in a nearby swamp. The investigation stalls...until a random love triangle provides a clue to finding her killer.

  • S02E07 Dying to Fit In

    • December 15, 2012
    • Investigation Discovery

    Sharon Bloom vanishes after leaving work to go out for lunch; her body is discovered 10 days later in a cornfield.

  • S02E08 He Came for Me

    • December 22, 2012
    • Investigation Discovery

    The 1980 stabbing death of a Colorado teenager is investigated.

  • S02E09 Wicked in the Windy City

    • December 29, 2012
    • Investigation Discovery

    Renee heads home from the gym on a cold, rainy Halloween; her favorite night of the year. The next day, she's found strangled to death on her bathroom floor. Police struggle to identify a killer. Could Renee be a victim of a 'trick or treat' gone bad?

  • S02E10 Crossed Dressed to Kill

    • January 5, 2013
    • Investigation Discovery

    Kacy Kay Ray leaves her parents' home after celebrating Christmas and vanishes. Days later, her frozen body is found in a field bludgeoned and stabbed, the victim of a gruesome rape. Will police pin the crime on the correct murderer?

Season 3

  • S03E01 Death Knocks

    • April 3, 2013
    • Investigation Discovery

    A woman is killed while showing her high-end home to a prospective buyer, and detectives try to find the culprit before he attacks again.

  • S03E02 Ring of Deceit

    • April 10, 2013
    • Investigation Discovery

    A missing woman's body is found in the trunk of her car two weeks after her disappearance.

  • S03E03 Never a Doubt

    • April 17, 2013
    • Investigation Discovery

    A man is convicted of murdering his mother-in-law, but his wife conducts her own investigation in hopes of proving his innocence.

  • S03E04 The Face of Justice

    • April 24, 2013
    • Investigation Discovery

    Children playing along the shore of the Wisconsin River come across garbage bags containing body parts.

  • S03E05 Murder at the Farmhouse

    • May 1, 2013
    • Investigation Discovery

    A dairy farmer and his wife are killed in Enderby, B.C.

  • S03E06 Kansas Killer

    • May 8, 2013
    • Investigation Discovery

    Investigating a cold case involving the murder of an elderly woman.

  • S03E07 Northern Nightmare

    • May 15, 2013
    • Investigation Discovery

    The disappearance of an Anchorage nurse is investigated.

  • S03E08 Not Forgotten

    • May 22, 2013
    • Investigation Discovery

    A 15-year-old cold case involving the arson murder of a young surfer is reopened.

Season 4

  • S04E01 Murder at the Met

    • October 1, 2013
    • Investigation Discovery

    A beautiful young violinist is murdered at the venerable Metropolitan Opera House in Manhattan and the story becomes an international scandal. Police interview everyone behind the scenes and the search is on for the real "Phantom of the Opera".

  • S04E02 One Stormy Night

    • October 8, 2013
    • Investigation Discovery

    With a thriving business and a baby on the way, a Florida couple is strangled to death in their home. Suspicions about drug smuggling and an aviation deal gone wrong lead detectives to Belize, but are they looking in the right direction?

  • S04E03 Nightmares in Babysitting

    • October 15, 2013
    • Investigation Discovery

    Fourteen-year-old Karen Slattery is brutally stabbed and raped while babysitting in South Florida's upscale Delray Beach. Police follow up on dozens of tips but the case goes cold. That is until a nearly identical crime strikes terror in nearby Boca Raton.

  • S04E04 Before He Kills Again

    • October 22, 2013
    • Investigation Discovery

    A woman's body is dumped alongside a road near Tampa, Florida. And within a year, the bodies of two more women are found at the side of the road. Detectives fear a serial predator is on the loose, but the search for the killer will take years.

  • S04E05 An Orphan's Ordeal

    • October 29, 2013
    • Investigation Discovery

    In Boston, 18-year-old Amy Roman is found slaughtered in her South End apartment. Police believe the victim knew her assailant. But when the case goes cold, her determined family undertakes an investigation of their own.

  • S04E06 A Secret Life

    • November 5, 2013
    • Investigation Discovery

    A pillar of the Haitian community in Spring Valley, New York, is gunned down in his driveway, and the suspects include the victim's terminally ill wealthy second wife, his alleged mistress, and her gun-toting ex-husband.

  • S04E07 No Reason to Die

    • November 12, 2013
    • Investigation Discovery

    When John and Nancy Bosco are shot at close range in their Bigfork, Montana home, the search is on for a cold-blooded killer. But with few clues and no suspects the case stalls. And John's mother eventually turns to an unorthodox source for help.

  • S04E08 Bad Things Happen to Good People

    • November 19, 2013
    • Investigation Discovery

    Bob Henry is gunned down in broad daylight outside the Tacoma, Washington warehouse where he works. The execution-style murder looks like a professional hit. But to solve the crime, police need to find the murder weapon.

  • S04E09 Bad for Business

    • December 3, 2013
    • Investigation Discovery

    Kathleen Smith is bludgeoned to death and her Tempe, Arizona home is then set on fire. Investigators have two suspects but no hard evidence to tie either to the murder. And it will take 15 years before a jailhouse tip finally leads cops to the killer.

  • S04E10 Into Thin Air

    • December 10, 2013
    • Investigation Discovery

    A glamorous flight attendant disappears and the story makes headlines. An intense search reveals few clues. But a graveside discovery eventually forces police to take a second look at some already familiar faces.

Season 5

  • S05E01 Identifying Remains

    • September 30, 2014
    • Investigation Discovery

    When a work crew uncovers a woman’s skull on a stretch of Florida highway, investigators try to determine who she is and find her killer. But it will take a bizarre discovery over a thousand miles away before the grizzly truth is finally revealed.

  • S05E02 What Happened in Vegas?

    • October 7, 2014
    • Investigation Discovery

    Single mother Donna Kitowski heads to a Las Vegas supermarket late at night but never returns.

  • S05E03 If Dogs Could Talk

    • October 14, 2014
    • Investigation Discovery

    When Cathy Lamb is brutally murdered in her Palm Beach, Florida home, the only witnesses are her three blood-soaked dogs. The gruesome scene baffles detectives. And with no suspects and no murder weapon, they have only their suspicions to go on.

  • S05E04 Who Took Polly Klaas?

    • October 21, 2014
    • Investigation Discovery

    During a slumber party, a man appears at 12-year-old Polly Klaas's bedroom door and abducts her at knife point.

  • S05E05 Where Murders Go Unsolved

    • October 28, 2014
    • Investigation Discovery

    The rape and murder of a 19-year-old journalism student in her bed is the latest in a string of unsolved homicides in a college town.

  • S05E06 Highway to Hell

    • November 4, 2014
    • Investigation Discovery

    Investigators believe a serial robber, rapist, and murderer is terrorizing cities up and down the west coast. And as the death toll rises, police jurisdictions in three states join the hunt for the ‘I-5 Killer.’

  • S05E07 Have You Seen Our Sister?

    • November 11, 2014
    • Investigation Discovery

    A single mother is murdered in Michigan and the police search for a man known only as "B."

  • S05E08 Texas Massacre

    • November 18, 2014
    • Investigation Discovery

    Five people who were abducted at a fast-food restaurant are murdered execution-style in Kilgore, Texas.

  • S05E09 The Ballad of Melissa Love

    • November 25, 2014
    • Investigation Discovery
  • S05E10 A Chance Encounter

    • December 2, 2014
    • Investigation Discovery

    A young woman is randomly gunned down in a Maryland suburb and it takes 25 years to find the killer.

  • S05E11 Who Do You Trust?

    • December 9, 2014
    • Investigation Discovery

    The killer of a 17-year-old Florida girl is finally found.

  • S05E12 When the Smoke Clears

    • December 16, 2014
    • Investigation Discovery

    A mother dies from cyanide poisoning and the investigation unravels a shocking story.

  • S05E13 Three Times the Pain

    • December 23, 2014
    • Investigation Discovery

    A popular college student is brutally stabbed to death during her first-ever night shift at a convenience store in Great Falls, Montana. And it will take a decade before an informant comes forward with a story that leads the cops to her killer.

Season 6

  • S06E01 Who Killed Daddy's Little Girl?

    • March 3, 2016
    • Investigation Discovery

    The murder of a pregnant 23-year-old Iowa woman is investigated.

  • S06E02 Mommy Speak for Me

    • March 10, 2016
    • Investigation Discovery

    The investigation into who killed an African American teen girl in Cleveland stalls until, decades later, a lucky break points to a suspect.

  • S06E03 California Girl Gone

    • March 17, 2016
    • Investigation Discovery

    The investigation into the murder of a 14-year-old girl, who was brutally beaten and set on fire.

  • S06E04 Dancing With the Devil

    • March 24, 2016
    • Investigation Discovery

    The investigation into the murder of a teacher in her Cleveland area home goes cold until investigators learn that a prison inmate claimed to have killed her while talking to his cellmate.

  • S06E05 An Angel Taken

    • March 31, 2016
    • Investigation Discovery

    The disappearance of a young woman from an Oregon parking lot is investigated.

  • S06E06 This Can't Be Happening

    • April 7, 2016
    • Investigation Discovery

    The discovery of a woman's body at an Orlando park is investigated.

  • S06E07 Screams of Silence

    • April 14, 2016
    • Investigation Discovery

    A man is suspected of murdering his pregnant wife due to a $300,000 life insurance policy.

  • S06E08 Somebody Knows

    • April 21, 2016
    • Investigation Discovery

    The investigation into a woman's murder requires 15 years, a deck of playing cards and a lucky break before it can be solved.

  • S06E09 Sheltered From the Truth

    • April 28, 2016
    • Investigation Discovery

    Debra Dill's bludgeoned body is discovered next to her car on a September morning in 1973, and it will take nearly two decades to put her killer behind bars.

  • S06E10 Where Her Future Ends

    • May 5, 2016
    • Investigation Discovery

    When the naked blood-soaked body of a young woman is found on the floor of her Orlando apartment, it's up to investigators to find her killer before he strikes again.

Season 7

  • S07E01 More Than a Sister

    • April 25, 2017
    • Investigation Discovery

    When 18-year-old Lisa Monza is murdered in San Lorenzo, Calif., investigators look for a connection to other unsolved murders in the area.

  • S07E02 Monster at the Door

    • May 2, 2017
    • Investigation Discovery

    After a respected widow is beaten to death in her Salt Lake City home, investigators suspect she knew her killer, but it will take 20 years before a set of children's fingerprints can put him at the scene of the crime.

  • S07E03 Why Isn't She Smiling?

    • May 9, 2017
    • Investigation Discovery

    A high school senior is murdered in her family's Minnesota farmhouse, but the case soon goes cold; years later, a fresh set of eyes spots an overlooked clue, but cold case detectives will need more to convict the killer.

  • S07E04 A Deadly Obsession

    • May 16, 2017
    • Investigation Discovery

    A New Hampshire man is shot dead through his screen door; investigators are stumped until they uncover a seething grudge and a culprit closer to home than anyone could have imagined.

  • S07E05 Gambling With Death

    • May 23, 2017
    • Investigation Discovery

    In southern Louisiana, a task force forms to hunt for a serial killer following a series of deadly home invasions.

  • S07E06 A Sister's Promise

    • May 30, 2017
    • Investigation Discovery

    The mutilated body of 17-year-old Lori Billingsley is found in a ditch on the outskirts of town, pointing to a sadistic killer on the loose in Oregon, but Billingsley's case goes cold, and it's up to her sister to pursue justice.