The Sundance Now drama’s empathy elevates it above more typical offerings in the genre even as its ending disappoints.

The Vanishing Triangle takes its name from media shorthand for an approximately 80-mile area in Eastern Ireland. For almost 20 years, from the late 70s to the late 90s, the Triangle suffered through several unsolved crimes. The victims, women ranging from teens to in their thirties, disappeared at an alarming rate. Additionaly, several murders of women in the area during the period were frequently linked in the press. Some speculated a serial killer’s (or serial killers’s) involvement, but the Gardaí—Ireland’s national police—never made such a declaration. As The Irish Times noted, “the ‘vanishing triangle’ phenomenon [is] a media creation rather than a Garda theory.” 

For Americans, the Missing and Murdered Indigenous Women crisis might be a useful frame for understanding the vanishing triangle. While considerably more widespread in the United States, both reflect a cluster of tragedies that have gone unanswered due to mistakes, indifference, implicit and explicit judgments about the victims, and systemic limitations. As a result, suggesting that these deaths and disappearances are the work of a serial killer is reductive. It risks ignoring many other societal factors that gave rise to an environment where such crimes occurred largely unchecked.

The Vanishing Triangle demonstrates an understanding of that delicacy while still seeking to dramatize the era. It proposes the specific series of crimes investigated in this series could indicate the work of serial killer. Still, it doesn’t ever widen the scope further or bring in true murdered or disappeared women to bolster its case. Additionally, the series works hard to highlight the other factors that may have undermined the Garda’s efforts. These elements include malignant elements like institutional arrogance, dismissal of sex workers as “worthy” victims, and police corruption. Additionally, it notes institutional and technical limitations like the lack of a countrywide coordinated missing persons database.

Starting a review with the three paragraphs above may set a reader’s teeth on edge. It does suggest the series might be more akin to homework than televised entertainment. Its thoughtfulness, however, is an asset, not a demerit. The Ivan Kavanagh series does not lack tension or strong characterization because it refuses the cheaper route. It provides the same drama and intensity that draw people to fictionalized accounts of true crime without the gross aftertaste of exploitation.

Lisa Wallace (India Mullen) is a newspaper reporter in Dublin. In an attempt to salvage a story, she reveals to her editors the home invasion and murder of her mother, a crime she witnessed. The newspaper lets her write the story, including how her tragic past informs the current situation. However, once she turns the piece in, the paper sensationalizes it with an enormous banner headline that makes Wallace’s trauma the focus.

The Vanishing Triangle demonstrates an understanding of that delicacy [of being respectful to victims] while still seeking to dramatize the era.

After the reporter’s exposure, Susan Reynolds (Laoise Sweeney) seeks out Wallace to help find her sister Amy. Amy, a girl in her 20s, missed the last bus home from a bar and had been missing since. The police largely waived off her disappearance as the act of promiscous woman still at her one night’s stand’s house. The reporter also receives a note from a man implying he both killed her mother and is responsible for Amy’s disappearance. Understandably frightened, Wallace takes the letter to the Gardaí, finding an ally in Detective David Burke (Allen Leech). His efforts, however, run aground of internal politics and threats to expose his secrets.

Kavanaugh and his team of women writers—Sally Tatchell and Rachel Anthony—and directors—Imogen Murphy and Laura Way—effectively humanize the victims and their families while exploring how they could be the people paid to protect the population could so easily write off these women. The series effectively frames people’s faces to capture subtle shifts in mood. They also well utilize medium and long shots to dial up tension and reveal danger to the audience before the characters can clock it.

Unfortunately, considering all The Vanishing Triangle does right, the series concludes on a bum note. It seems to be rushing its conclusion after six episodes of deliberate and tightly managed pacing. It runs two brief monologue scenes between moments in the credits, like a student sneaking in just one more thought on an essay test. Moreover, the fate of one character who seemingly has finally fully come into their own feels both unsatisfyingly abrupt and echoes an unfortunate trope. After managing so many potentially disappointing elements so well for almost 270 minutes over six episodes, fumbling the last ten sends the audience off with a sour taste.

Nonetheless, it isn’t nearly enough to not recommend the series. Mullen and Leach give the kind of performances that make acting seem easy. They slip into the characters that well. In a cast populated by strong supporting performances, Philip O’Sullivan deserves a special shout-out as a figure symbolic of the Old Guard’s rot and limitations. His performance captures both how dangerous such people can be and how quickly they can be made weak in the face of resistance. A poor ending is a poor ending, for sure, but The Vanishing Triangle does too much well to be written off for its conclusion.

The Vanishing Triangle stalks Ireland’s bogs on AMC+ starting October 26.