The Final Problem (2026), originally titled El problema final, is a Spanish Netflix mystery series based on the novel by Arturo Pérez-Reverte. Set on an island near Mallorca in 1959, the four-episode story begins when a storm leaves 13 people stranded at a secluded hotel. One guest is found dead, and a former actor famous for playing Sherlock Holmes is drawn into the investigation. This spoiler-free review explores the premise, cast, period atmosphere and where to watch the series.
The Final Problem (2026): release date, episodes and key details
The Final Problem premiered on Netflix on September 25, 2026. Its original Spanish title is El problema final. The limited-series format consists of four episodes, making it a compact murder mystery rather than an ongoing detective procedural with multiple unrelated cases.
| English title | The Final Problem |
|---|---|
| Original title | El problema final |
| Premiere | September 25, 2026 |
| Episodes | 4 |
| Genre | Period mystery, crime thriller |
| Country | Spain |
| Director | Félix Viscarret |
| Adapted from | The novel by Arturo Pérez-Reverte |
| Cast | José Coronado, María Valverde, Martiño Rivas, Maribel Verdú |
| Streaming | Netflix |
The story’s historical setting is integral to its tension. The characters have limited ways to communicate with the outside world, and when a violent storm separates them from Mallorca, they must rely on their own memories, observations and judgment.
What is The Final Problem about? A spoiler-free plot summary
It is spring 1959. Thirteen people have gathered on a small Mediterranean island off Mallorca, where an isolated hotel offers the promise of privacy and calm. That promise does not last. A severe storm arrives, leaving the group unable to depart or seek help easily from the mainland.
Then an English visitor, Elisa Mander, is found dead. The circumstances initially suggest one explanation, but troubling inconsistencies raise the possibility that her death was not a suicide. The other guests have nowhere to go, and everyone becomes a potential witness or suspect.
Among them is Basil, a retired actor who once played Sherlock Holmes on screen. His fame belongs largely to the past, but being associated with one of fiction’s great detectives suddenly becomes more relevant than he might have imagined. He is asked, or drawn, into unraveling a real mystery even though he has never been a professional police investigator.
That is an appealing twist on the traditional amateur-sleuth formula. Many detective stories feature people with seemingly extraordinary observational skills. Here the protagonist’s reputation comes from pretending to possess those skills for an audience. He must discover whether any of his experience interpreting mysteries on camera can help him understand a crime with actual consequences.
As the storm continues, secrets surface and simple accounts of the dead woman’s final hours become increasingly difficult to reconcile. Viewers are invited to consider who had the opportunity to act, whose stories hold together and whether the most obvious suspect is necessarily the right one.
A classic locked-room mystery with a clever television twist
The Final Problem draws on a familiar and effective tradition: the closed-circle mystery. The number of suspects is limited, the setting is confined and the murder appears to be a puzzle that can be solved by careful attention to details. Agatha Christie remains the best-known reference point for the form, but the appeal is broader than any single writer’s work.
By restricting the characters’ movement, the series makes ordinary interactions more suspicious. A private conversation becomes significant because everyone is aware of everyone else’s presence. A missing piece of information carries greater weight when there are few opportunities for an outsider to have intervened.
The 1959 setting also means there are no convenient smartphones, instant databases or contemporary surveillance systems to eliminate possibilities immediately. Instead, interviews, timelines and small physical clues become central to the story. Such constraints allow audiences to investigate alongside the characters.
The distinctive comic tension comes from Basil himself. Other people may treat him like Sherlock Holmes because they remember his television role, yet solving a scripted case is very different from interpreting contradictory human behavior. The actor must learn where performance ends and genuine reasoning begins.
The Final Problem cast: José Coronado, María Valverde and Maribel Verdú
José Coronado leads the cast as Basil. The character’s combination of faded fame and unexpected responsibility provides a strong entry point into the mystery. He may recognize detective-story conventions, but his personal experience as an actor does not automatically grant him the authority or knowledge of an actual investigator.
María Valverde plays Adela Figueroa, another figure whose presence matters within the small island community. Her role adds another layer to the shifting relationships among the guests. In a story where appearances may mislead, the viewer’s first impression of a character can become part of the puzzle.
Martiño Rivas portrays Fauche, a would-be mystery writer who assists Basil. Having a character who wants to create detective fiction alongside someone associated with a fictional detective gives the show a self-aware dimension: both men must approach a case without the benefits of an author’s predetermined solution.
Maribel Verdú appears as Mrs. Auslander, who runs the hotel. Keeping a secluded establishment functioning during a storm would be difficult enough; adding a suspicious death makes every interaction between staff and guests fraught with tension.
The wider cast includes Gonzalo de Castro, Cristina Kovani, José Condessa and Pepón Nieto. Because the mystery revolves around a comparatively small group, these supporting characters are not merely background decoration. The way each responds to suspicion helps keep the central question alive.
Is The Final Problem based on a book?
Yes. The Netflix limited series adapts Arturo Pérez-Reverte’s novel El problema final. The Spanish author is known for fiction involving mysteries, history, intellectual games and characters forced to question what they believe they know.
An adaptation of a literary puzzle faces a particular challenge. The novel can control when a reader learns a fact through narration, while television must decide which clues to reveal visually. Camera placement, dialogue and the order of scenes can give away information too early or obscure it so thoroughly that the eventual solution feels unearned.
The four-episode structure offers enough time to develop the suspects without stretching the central investigation indefinitely. Viewers familiar with the book may enjoy comparing how the series treats Basil and how it manages the rhythm of clue discovery. Those who have not read it can follow the show as an independent mystery.
The series is directed by Félix Viscarret, and Netflix identifies it as a historical thriller combining investigation, atmosphere and a large ensemble of recognizable Spanish performers.
The Final Problem review: who should watch it?
The premise makes The Final Problem a promising choice for fans of classic whodunits, period crime mysteries and self-aware detective fiction. The limited setting encourages viewers to scrutinize every account of the crime, and the lead character’s fictional-detective background provides an intriguing contrast with the seriousness of a real death.
Those who prefer character-driven suspense to rapid action may appreciate its emphasis on interviews, relationships and small inconsistencies. A four-episode run also makes it relatively approachable for someone seeking a contained weekend mystery.
Conversely, audiences expecting elaborate car chases or a violent action thriller may find the slower, conversational approach less immediately engaging. The story is designed around discovering the truth among a set of suspects rather than escalating physical spectacle.
This overview draws on Netflix’s official synopsis, trailer and cast information. It deliberately avoids an invented personal rating and does not claim to have watched an ending that the cited material does not establish.
Where to watch The Final Problem (2026)
The four episodes are on Netflix in regions where the series is available. Available languages and subtitles differ by location and account. The distributor has also shared the official YouTube trailer, which is free to view without confusing it with access to full episodes.
The Final Problem: frequently asked questions
When was The Final Problem released? September 25, 2026.
How many episodes are there? Four.
Is this a Sherlock Holmes adaptation? Not directly. The main character is an actor who formerly played Sherlock Holmes, but the case is a separate story.
Who plays Basil? José Coronado.
Is it based on a novel? Yes, Arturo Pérez-Reverte’s El problema final.
Where can I watch the trailer? On Netflix’s official YouTube channel.
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Find more mysteries in Reviews and TV Series.
Sources: Netflix — official trailer and cast release; Netflix — series announcement and setting; Netflix title page.
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