Young Sherlock (2026) Review: Holmes Before the Legend

Is Young Sherlock worth watching?

Yes. Young Sherlock is a brash, energetic origin story that makes a pre-genius Sherlock Holmes enormous fun to spend time with, largely thanks to Hero Fiennes Tiffin’s live-wire lead. Its fast pace, period swagger and unlikely partnership with the young James Moriarty give the familiar character a genuinely fresh angle. The reservation is that the mystery plotting is looser than the style, and purists who want a careful, deductive Holmes will find this version far too irreverent.

What is Young Sherlock about?

At 19, Sherlock Holmes (Hero Fiennes Tiffin) is brilliant, restless and self-destructive, a troublemaker who is packed off to Oxford in the 1870s. There he quickly lands in the middle of a murder investigation, as its prime suspect. To clear his name, he forms an uneasy alliance with a clever scholarship student, James Moriarty (Dónal Finn), and the pair are pulled into a breakneck chase across Victorian England and beyond, hunting a missing relic tied to a conspiracy uncomfortably close to home.

Created by Matthew Parkhill, Young Sherlock is a British series in English for Prime Video, with Guy Ritchie bringing the kinetic style of his Sherlock Holmes films. The cast also includes Zine Tseng, Joseph Fiennes, Max Irons and Colin Firth. This review covers the first season of 8 episodes; the series is continuing.

Hero Fiennes Tiffin plays Holmes as a live wire

This Sherlock is not yet the cool, composed detective of legend. Fiennes Tiffin plays him as a young man whose brain runs faster than his judgement, cocky and funny, capable of flashes of extraordinary insight and equally capable of making every situation worse. The performance is full of physical energy and quick wit, and it gives the series a sense of Holmes as someone still discovering what his gifts are for.

The pairing with Moriarty is the show’s cleverest idea. Dónal Finn plays him as sharp, ambitious and conscious of class in a way Sherlock never has to be, and their partnership crackles with rivalry and mutual respect. Knowing what these two names mean in detective fiction gives every scene between them an extra layer of tension, and the show uses that dramatic irony shrewdly without leaning on it too heavily.

Guy Ritchie pace in a Victorian setting

Stylistically, the series is unmistakably in the Ritchie mould. It moves quickly, with rapid cutting, playful flourishes, anachronistic needle-drops and a taste for action set pieces. Oxford’s colleges and Victorian streets are handsomely rendered, and the chase beyond England widens the canvas. The approach suits an origin story about a young man who cannot sit still, and it keeps the eight episodes brisk.

A strong supporting cast, including Colin Firth, Joseph Fiennes, Max Irons and Zine Tseng, gives the frenzy some ballast, and the older actors in particular lend weight to a story that could otherwise feel weightless.

Where the mystery takes a back seat

The show’s enthusiasm for momentum sometimes costs it as a mystery. Deductive puzzles take second place to chases and conspiracies, and some of the plotting relies on coincidence and convenient discoveries rather than the rigorous reasoning that defines Holmes. The tone can also feel more modern than Victorian, which will charm some viewers and irritate others. It is best enjoyed as an adventure rather than a whodunit.

Who should watch Young Sherlock?

It suits viewers who enjoy period adventure, energetic mysteries and fresh takes on familiar characters, and fans of Guy Ritchie’s films will feel at home. Eight episodes make a manageable binge. It is rated for older teens: expect action violence, murder and some strong language, but nothing especially graphic.

For more in a similar key:

• Luther for another brilliant, self-destructive detective at the centre of a British crime series.
• Dept. Q for an unconventional investigator with a sharp mind and a difficult personality.
• More puzzles and investigations in our mystery section.

The verdict

Young Sherlock is an irreverent, fast-moving reinvention of Sherlock Holmes that works because it commits fully to its swagger and gives Holmes and Moriarty a compelling partnership. The mysteries are lighter than the style, but as a stylish period adventure it is consistently entertaining.

Rating: 4/5