Spoilers ahead for The Final Problem. Netflix’s The Final Problem takes the classic locked-room mystery and gives it an unusual twist: its detective is a retired actor who became famous for playing Sherlock Holmes. When a British tourist is found dead at an isolated hotel, Benjamin Basil has to use the detective skills he learned for the screen to investigate a real murder.
The four-part Spanish miniseries is based on Arturo Pérez-Reverte’s novel El problema final, but the adaptation does not follow the book exactly. The Netflix version changes the setting, year, number of people trapped at the hotel and several character details. That difference is important when explaining the ending.
What Is The Final Problem About?
The story takes place in the spring of 1959. A violent storm leaves thirteen people trapped at an isolated hotel on an island near Mallorca. With the weather cutting the hotel off from the outside world, nobody can simply leave.
Then Elisa Mander, a British tourist, is found dead.
At first, her death appears to be suicide. Benjamin Basil, however, notices that some details do not make sense. What looks like a simple death gradually becomes a murder investigation.
The situation is especially strange because Basil is not a professional detective. He is a retired actor who became famous for playing Sherlock Holmes. His knowledge of deduction comes from years of portraying the fictional detective on screen.
Now he has to find out whether the person responsible for Elisa’s death is one of the people trapped inside the hotel.
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| Title | The Final Problem |
|---|---|
| Year | 2026 |
| Genre | Crime, Mystery, Thriller, Drama |
| Language | Spanish |
| Director | Félix Viscarret |
| Main Cast | Jose Coronado, María Valverde, Martiño Rivas, Maribel Verdú, Gonzalo de Castro |
| Based On | El problema final by Arturo Pérez-Reverte |
| Episodes | 4 |
| Streaming | Netflix |
Why Is the Hotel So Important?
The storm creates the perfect locked-room mystery.
Thirteen people are trapped together, and there is no easy way for an outsider to enter the island and commit the crime before disappearing. This means that the killer is most likely already among them.
That changes the mood inside the hotel. Every guest becomes suspicious. A private conversation can look like a secret meeting. A lie about someone’s past can suddenly look like evidence of murder.
Basil quickly realizes that solving the crime will not be as simple as finding the person with the strongest motive.
Almost everyone has something to hide.
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Who Is Benjamin Basil?
Benjamin Basil is the heart of the series.
He spent much of his career playing Sherlock Holmes, but he repeatedly reminds people that he is only an actor. He never actually possessed Holmes’s life or professional experience.
That creates one of the show’s best ideas. Basil has spent years pretending to be a detective, and now real people expect him to solve a real murder.
Francisco Foxá, a young thriller writer, becomes his closest companion during the investigation. Their relationship also echoes the familiar detective-and-companion setup found in classic mystery stories.
Why Does Everyone Become a Suspect?
The mystery becomes complicated because there is no single obvious suspect.
Adela Figueroa is mysterious. Raquel Ausländer, the hotel manager, is trying to keep control of the frightened guests. Foxá is deeply interested in the investigation. Other guests, including Vicky, Fonseca, Toni and Dr. Seruya, also have their own secrets.
Then things become even worse for Basil when a murder weapon appears in his room.
Suddenly, the detective is also connected to the crime.
The killer seems to understand how Basil thinks. That makes the investigation dangerous because a carefully planted clue can send him toward the wrong person.
The Murder Weapon in Basil’s Room
The appearance of the murder weapon is one of the moments that increases the pressure on Basil.
If the killer can place evidence in Basil’s room, it means someone has been able to move around the hotel without being noticed. It also suggests that the murderer may be deliberately playing with the investigation.
Netflix’s second episode description specifically says that Benjamin becomes afraid the killer will strike again after a murder weapon appears in his room. Vicky also makes an accusation, but the evidence does not completely support it.
This tells Basil something important: not every clue is genuine.
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The Mystery Is Really About Identity
The deeper Basil investigates, the more the question changes.
It is no longer simply:
Who killed Elisa Mander?
The more important question becomes:
Who are these people really?
The characters are constantly presenting versions of themselves. Some hide their pasts. Some hide relationships. Some pretend to be less important than they really are.
Basil therefore has to look beyond what people say about themselves. Their behavior, history and identities may tell a completely different story.
What Happens in the Final Episode?
The fourth episode moves the mystery toward its final stage. Benjamin still cannot forget what happened at Santa Águeda, while the filming of a new movie exposes more about the characters and helps bring the mystery to a conclusion. Netflix describes the episode as the point where the characters’ true colors are revealed and the final problem is resolved.
This is more than a normal detective ending because the series keeps returning to the idea of acting.
Basil is an actor. He spent years playing Sherlock Holmes.
The people around him are also, in a sense, acting. They are playing innocent guests, frightened victims, grieving friends or harmless strangers while keeping important information hidden.
The hotel begins to feel almost like a stage where everyone has been given a role.
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Who Is Behind the Murder?
This is where it is important to separate the Netflix series from the original novel.
In Arturo Pérez-Reverte’s original novel, the major identity twist reveals that the woman living as Vesper Dundas is actually Edith Mander. Edith is responsible for the murders and has been using another identity as part of a revenge plan connected to her past and Hans Klemmer.
The novel is set in 1960 on the Greek island of Utakos, where nine people are trapped by a storm. The first victim is Edith Mander. These details are different from Netflix’s version, which moves the story to an island near Mallorca, sets it in 1959, increases the trapped group to thirteen and changes the first victim’s name to Elisa Mander.
Because of these changes, the book’s ending should not simply be copied onto the television series character by character.
In other words, it is not safe to say that Adela Figueroa is automatically the television version of Edith Mander just because that is how the novel’s identity twist works. The Netflix adaptation changes enough of the story that its characters need to be judged on the show’s own terms.
What Is the Big Twist in the Original Novel?
The novel provides useful background for understanding what kind of mystery the series is adapting.
In the book, Edith Mander and Vesper Dundas are traveling together. After the murder investigation appears to end without a clear solution, Basil later works out that the woman believed to be Vesper is actually Edith.
The two women have switched identities.
The woman who appears to have been Edith is actually Vesper, while the surviving woman has been hiding behind Vesper’s identity.
Basil eventually connects the identity switch with the murders and Edith’s desire for revenge. The original novel’s solution is therefore based on a combination of murder, deception and a carefully hidden identity.
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Why Is the Title The Final Problem Important?
The title is a clear reference to Sherlock Holmes and the famous tradition surrounding his final case.
But it also describes Basil’s personal challenge.
He spent his career pretending to be Holmes. Now he faces a mystery that resembles one of the cases he used to perform on screen.
The irony is simple: the man who was never a real detective has to solve a real detective problem.
His final challenge is not only finding the killer. He has to work out which parts of the story are real and which parts are performances designed to fool him.
What Happens to Basil?
Basil begins the story as a reluctant investigator. He knows that his reputation comes from acting rather than actual detective work.
As the investigation continues, however, he becomes more confident in his ability to examine evidence and question the assumptions everyone else has accepted.
His experience as an actor becomes useful in an unexpected way. Basil understands performance. He knows that people can say one thing while trying to make others believe something completely different.
That helps him see through the false appearances surrounding the murder.
Yes. The miniseries is based on Arturo Pérez-Reverte’s novel El problema final. However, the Netflix adaptation changes several characters, locations and story details.
The Netflix adaptation takes place at an isolated hotel on an island near Mallorca. A storm traps the guests there and prevents them from easily leaving.
In the Netflix series, Elisa Mander is found dead at the hotel. Her death initially appears to be a suicide but Basil begins to suspect that she was murdered.
Basil notices that the circumstances surrounding Elisa Mander’s death do not make sense. Because everyone is trapped at the hotel, he realizes that the murderer could be one of the people inside.
The discovery puts Basil under pressure because it suggests that someone is deliberately framing him or manipulating the investigation. It also shows that the killer may understand how Basil thinks.
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