On July 11, 2006, Mary Cooper and her daughter Susanna Stodden set out for a routine hiking trip in Washington’s Cascade Mountains, unaware that their decision to change destinations would become a central detail in an unsolved double homicide. Hours later, both women were discovered shot in the head along the remote Pinnacle Lake Trail, with their belongings nearby and no obvious explanation for the violence. Unsolved Mysteries, hosted by Jordan Murphy, reconstructs their final known movements, examines the investigation’s most significant leads, and follows a grieving family’s determination to identify whoever was responsible. The result is a deeply personal true-crime investigation that balances the unsettling circumstances of the murders with the human consequences of a case that has remained unresolved for two decades.
The reconstruction of July 11 is particularly effective because it establishes how the trail’s geography complicated nearly every stage of the investigation. Mary and Susanna originally intended to hike Mount Pilchuck but changed their plans after Mary’s husband, Dave, warned about lingering snow. Their arrival at the Pinnacle Lake trailhead around 10 a.m., the discovery of their bodies around 1:30 p.m., and reports of gunshots near 1 p.m. provide investigators with a relatively narrow timeline. However, the steep terrain, limited access, lack of cellular service, and uncertainty surrounding the women’s movements leave important gaps. The account of responding officers protecting the scene overnight, while rain threatened to destroy potential evidence, demonstrates how an isolated outdoor location can turn a homicide investigation into an enormous logistical challenge.
Detective Dave Billio’s contributions give the investigation much of its credibility and structure. His explanations of the witness accounts, tracking evidence, and possible escape routes help distinguish documented findings from theories developed over years of investigation. Particularly intriguing are signs that someone traveled directly down the mountainside rather than following the trail’s switchbacks, along with a witness report of a small red vehicle speeding down the access road. Neither observation has been conclusively connected to the murders, and Billio generally acknowledges those limitations. The presentation nevertheless occasionally encourages viewers to interpret these ambiguous details as pieces of a coordinated escape, even though investigators cannot establish whether they involved the perpetrator.
The examination of Dave Stodden as an early suspect introduces one of the investigation’s most uncomfortable dimensions. Although multiple witnesses placed him in Seattle on the day of the murders, detectives continued exploring his possible involvement, including a theory that he might have hired someone else. The discussion of three polygraph examinations, with the first two producing disputed or inconclusive results and the third reportedly passed, illustrates the uncertainty surrounding that investigative approach. Dave’s frustration with the authorities is understandable, particularly given his account of their initial interactions and the attention directed toward him while he was grieving. The program benefits from allowing both Dave and Billio to explain their perspectives, although it could more explicitly emphasize that polygraph results are not reliable proof of guilt or innocence.
The possibility of a random predator becomes increasingly important as investigators find no apparent enemies, clear robbery motive, or established evidence of sexual assault. An FBI behavioral assessment reportedly suggested that the killer might have waited along the trail for suitable victims, while Billio considers whether someone familiar with the area deliberately selected the isolated location. The discussion of serial killer Israel Keyes adds another disturbing possibility because his known behavior included traveling extensively, targeting strangers, and using remote locations. Yet the investigation also identifies significant inconsistencies, particularly the failure to conceal the victims’ bodies, and ultimately reports DNA findings excluding Keyes as a contributor to the recovered profile. The segment is strongest when presenting these contradictions rather than treating similarities in criminal behavior as evidence of responsibility.
The most substantial investigative development involves DNA recovered from beneath Susanna’s fingernails. Evidence preserved during the original autopsy was resubmitted for testing in 2020, producing a partial male DNA profile that investigators could compare with known samples. Those comparisons excluded Dave, Susanna’s boyfriend Norm, and Keyes as contributors, providing a meaningful advance after years without an identified suspect. Importantly, the program acknowledges that the profile has not established who committed the murders or even definitively identified the source as the killer. Its discussion of possible future testing and investigative genetic genealogy offers legitimate hope, although the presentation would benefit from additional detail about the profile’s limitations, the possibility of incidental DNA transfer, and what further analysis might realistically accomplish.
Dave’s personal account ultimately provides the investigation with its greatest emotional weight. His memories of Mary and Susanna as compassionate educators, his efforts to distribute thousands of flyers, and his decision to carry their ashes to meaningful places around the world reveal the enduring impact of the murders without reducing the women to crime-scene evidence. His continued visits to Pinnacle Lake, where memorial signs and a bench preserve their memory, are especially affecting. The closing appeal for information gives the story a practical purpose beyond recounting an unresolved tragedy. Although the production occasionally relies on dramatic questions and ominous possibilities to maintain suspense, its strongest moments come from the quieter reflections of a father who has spent years pursuing answers while refusing to surrender the rest of his life to grief.
Pros
- Provides a detailed chronological reconstruction of Mary Cooper and Susanna Stodden’s final hike, incorporating witness sightings, reported gunshots, emergency calls, and investigative timelines.
- Effectively explains how Pinnacle Lake Trail’s isolation, difficult terrain, limited communications, and changing weather complicated the initial response and preservation of evidence.
- Features substantial contributions from Detective Dave Billio, who distinguishes confirmed investigative findings from uncertain witness observations and competing theories.
- Examines the investigation into Dave Stodden, including his documented alibi, the hired-killer hypothesis, and the controversy surrounding repeated polygraph examinations.
- Evaluates Israel Keyes as a possible suspect while acknowledging important inconsistencies and the subsequent DNA findings that excluded him as a contributor to the recovered profile.
- Clearly identifies the partial male DNA profile recovered from Susanna’s fingernails as a meaningful forensic development without claiming that it establishes the perpetrator’s identity.
- Gives Dave Stodden considerable room to discuss his wife and daughter, his relationship with investigators, and his continuing efforts to obtain justice.
- Concludes with a purposeful appeal for information that could help investigators advance the unresolved case.
Cons
- The discussion of a possible predator waiting for vulnerable hikers relies heavily on behavioral interpretation rather than direct evidence establishing the killer’s motive or movements.
- The off-trail tracks and speeding red vehicle receive considerable attention despite having no confirmed connection to the murders.
- The polygraph discussion could more clearly explain the scientific limitations of the examinations and why their results cannot establish innocence or guilt.
- The forensic segment provides limited technical detail about the partial DNA profile, including its evidentiary limitations and the requirements for future genetic genealogy testing.
- Some dramatic narration and hypothetical scenarios encourage speculation about the killer’s intentions without substantially advancing the factual investigation.
Unsolved Mysteries delivers a compassionate and absorbing examination of a double homicide that remains disturbing precisely because so little is known about the person responsible. Its careful reconstruction, firsthand investigative perspectives, and meaningful discussion of DNA evidence provide considerable value, while Dave Stodden’s reflections ensure that Mary and Susanna remain central to the story. Although several theories extend beyond what the available evidence can establish, the program succeeds in communicating both the complexity of the investigation and the importance of keeping the case in public view.
