Netflix’s ‘The Final Problem’ Release Date, Cast, Plot and Everything Else We Know About the Project That Unmasks a Sherlock Holmes Actor as an Unlikely Murder Detective

Netflix is diving into Agatha Christie territory with a fresh twist, and this time the detective on the case is a man who only knows how to solve crimes because he once played one on screen. ‘The Final Problem’ is Netflix’s new five episode miniseries based on Arturo Pérez-Reverte’s bestselling novel, and it is shaping up to be one of the streamer’s most intriguing mystery drops of the year.

The series blends a classic locked room whodunit with a meta twist on the detective genre itself, and fans of moody, character driven thrillers are already buzzing about it. Here is everything currently known about the release date, trailer, plot, and cast of ‘The Final Problem’.

‘The Final Problem’ Release Date and Where to Watch

Netflix has officially set The Final Problem for a September 25, 2026 release date. Multiple outlets have confirmed the same premiere window, with one report noting the series is set to premiere Friday, September 25, 2026, on Netflix.

There has been some minor confusion online about the episode count, since one report describes it as a four episode limited series while Netflix’s own announcement describes the miniseries as consisting of four episodes in one place, though the original press rollout described it as a five episode miniseries. Either way, this is a bingeable, limited run event rather than an ongoing series, and it will be available exclusively on Netflix worldwide.

Given the streamer’s track record with foreign language mysteries, ‘The Final Problem’ is expected to land in the platform’s Top 10 charts shortly after launch, especially among viewers who gravitate toward slow burn, Christie style ensemble thrillers.

‘The Final Problem’ Trailer Sets a Stormy, Sherlock Holmes-Inspired Mood

Netflix has already released promotional footage to build anticipation. A date announcement trailer for the series was released on Netflix’s official YouTube channel, followed later by a full length trailer.

The official Netflix listing confirms there are two pieces of footage available now, described as a Limited Series Teaser and a Limited Series Trailer for The Final Problem. The tone of both leans heavily into atmosphere, with howling coastal winds, a crumbling old hotel, and a cast of increasingly paranoid guests.

Critics have already latched onto the show’s playful premise. One outlet described the footage as introducing a delightfully offbeat Sherlock Holmes adaptation that sees an actor known for playing the Great Detective try to solve a real life murder in a remote, inaccessible location. That self aware wink at the mystery genre appears to be central to the show’s identity, separating it from a straightforward period procedural.

‘The Final Problem’ Plot Traps Thirteen Guests With a Killer

The setup is pure isolated island intrigue. According to Netflix’s own synopsis, in the spring of 1959, thirteen people find themselves stranded by a violent storm on a small island off the coast of Mallorca, cut off from the outside world at a secluded hotel.

Things take a dark turn quickly. A quiet English tourist named Elisa Mander is found dead, and what initially appears to be a suicide soon reveals itself to be a murder. The English tourist detail is echoed elsewhere, with another report confirming an English tourist is found dead, and her apparent suicide is revealed to be murder.

That is where the show’s central hook kicks in. Basil, a retired actor who once portrayed Sherlock Holmes on the big screen, finds himself almost unwittingly tasked with uncovering the truth behind what happened. Netflix’s official page frames the premise similarly, describing a fading actor who must use his famous character’s detective skills to solve a suspicious death at an isolated hotel where everyone becomes a suspect.

The source material gives the story extra credibility among mystery fans. ‘The Final Problem’ is based on the 2023 novel by Arturo Pérez-Reverte, an author well known for genre fiction rooted in classic detective tropes, which should appeal directly to viewers who enjoy shows like ‘In For A Murder’ or ‘A Widow’s Game.’

‘The Final Problem’ Cast Brings a Star-Studded Spanish Ensemble

Leading the cast as the washed up actor turned reluctant sleuth is José Coronado. He is joined by a deep ensemble that includes María Valverde, Maribel Verdú, Gonzalo de Castro, Cristina Kovani, José Condessa, and Pepón Nieto, alongside Martiño Rivas.

Netflix’s official title page rounds out the roster further, listing Jose Coronado, María Valverde, Martiño Rivas, Gonzalo de Castro, Pepón Nieto, Cristina Kovani, José Condessa, Daniel Holguín, Michael Stobbe, and Maribel Verdú as the core cast. It is a stacked lineup for Spanish television, mixing veteran dramatic actors with rising faces familiar to Netflix’s international audience.

Behind the camera, the series comes from a team with a strong pedigree in Spanish language storytelling. Félix Viscarret directs all five episodes from scripts adapted by Alberto Macías, Carlos Molinero, and Marisol Farré, while Fernando Bovaira produced the series for Mod Producciones, with Urko Errazquin serving as executive producer.

That combination of a proven producing team and a genre savvy premise is a big reason ‘The Final Problem’ has generated early buzz among mystery fans who track Netflix’s international slate closely. With its Agatha Christie inspired setup and a lead character whose entire skill set comes from having played a detective on screen, this is shaping up to be one of the more clever twists on the whodunit format in recent memory.

Now that the island is locked down, the storm has hit, and the body has been found, who do you think actually killed Elisa Mander at that isolated hotel in ‘The Final Problem’?