Before Sherlock & Poirot, Another Detective Starred In One Of The Best Prequel Series Of All Time

Published Aug 29, 2026, 7:00 AM EDT

El is a Junior TV Features Editor for ScreenRant, with previous experience as The Mary Sue's UK and Weekend Editor. She holds a Bachelor's in International Media and Entertainment Management, as well as an MA and Ph.D. in Creative Writing. There is little she loves more than discussing her favorite TV shows with fellow fans. One day, she hopes to publish an original fantasy novel.

Years before Prime Video's Young Sherlock and the BBC and BritBox's upcoming Hercule Poirot prequel series, ITV produced one of the best detective-centric prequel shows of all time. For characters as famous and well-established as Arthur Conan Doyle's Holmes and Agatha Christie's Poirot, watching them as their younger selves can allow audiences to see a different side of them. How did Sherlock Holmes come to be such an arrogant, chaotic force of nature? How did Poirot establish himself as the ultimate gentlemanly detective?

Of course, Sherlock and Poirot have influenced countless other fictional detectives, both classic and modern, especially in the UK. Sleuths (both professional and amateur) like Midsomer Murders' John Barnaby, Father Brown, Prime Suspect's Jane Tennison, and even Ludwig's puzzle setter John Taylor can all trace their roots back to Doyle's and Christie's works. The same is true for Colin Dexter's Endeavour Morse, a British detective who first debuted in the 1975 novel Last Bus to Woodstock and would go on to star in 12 more books, as well as a self-titled TV series, the much-loved Inspector Morse.

John Thaw's portrayal of the titular detective was so successful that the show spawned two additional spinoffs years after its original finale: Inspector Lewis, a sequel series focusing on Morse's loyal sergeant, now a Detective Inspector in present-day Oxford, and a fascinating prequel series, Endeavour, which follows the soon-to-be Chief Inspector during his early days as a Detective Constable in the '60s and '70s as he deals with police corruption, stubborn colleagues, lost loves, and gruesome, tragic murder cases.

Endeavour Is One Of This Century's Best British Detective Dramas

Regardless of its connection to Inspector Morse, Endeavour is one of this century's most memorable and impressive detective dramas. It fully immerses viewers in its period setting, not only through intricate costumes, sets, and music (the score is stunning), but also in its storytelling, narrative themes, and the way the characters interact with one another, especially within the police force.

The writing is gorgeous and haunting. Each feature-length episode introduces a new investigation, examining Britain's ever-present class divide, Oxford University's exclusive and at times horrifically toxic atmosphere, different political groups and movements, and the lives of everyday British people trying to survive in a torn, post-War world. There to solve every case are DC Endeavour Morse (Shaun Evans) and his superior officer, DI Fred Thursday (Roger Allam), whose partnership is the show's foundational heart and one of the best in detective fiction, period.

Endeavour is currently #188 on IMDb's Top 250 TV Shows list with an 8.6/10 rating, based on 38K reviews.

Evans and Allam both play their parts perfectly; Allam is stalwart and dependable as DI Thursday, a man who's been deeply traumatized by his wartime experiences but tries to do his best for his family, his colleagues, and the show's victims. Endeavour would be nowhere without Evans' performance as Morse, however.

While he approaches the character differently than his predecessor, Evans is undeniably captivating in the role, haunted by his past and driven to succeed in his future. His cleverness and occasional arrogance aren't off-putting. There's something incredibly human about him; what he truly wants is to solve each case and prove himself as a detective, all the while struggling with his loneliness. Endeavour is the ultimate example of a prequel done right, the rare show that enhances its lead character and the show it spun off from.

Which Other Famous Detectives Deserve A Prequel Series?

There are plenty of other detectives that deserve and would even benefit from a prequel series. Endeavour proves that shows like this can work, even when the detectives aren't world-famous literary icons. Like Endeavour's Morse, Prime Suspect's Jane Tennison (originally portrayed by the incredible Helen Mirren) has already earned a prequel series. Other British detectives, like Vera's DCI Vera Stanhope, Agatha Christie's Miss Marple, G.K. Chesterton's Father Brown, Foyle's War's DCS Foyle, Luther's DCI John Luther, and more, could all benefit from exploring their characters further in their younger years, too.

Prequels work best when they're character-focused rather than plot-focused. It's about following these people on their journey and learning what makes them tick; no genre is arguably more character-driven and even wholly dependent on its characters' likability than detective fiction. It's all well and good to plot a convincing mystery, but without a compelling character to guide viewers (or readers) through that mystery, what will keep them coming back for more? As Endeavour proves, the right detective will always find an audience, no matter where they are in their career.

Endeavour is available to stream via PBS.