Midsomer Murders: 10 Actors You Had No Idea Were On The Show

Midsomer Murders is one of Britain's longest-running detective shows, having aired on ITV since 1997. It stars Neil Dudgeon as Detective Chief Inspector John Barnaby, who took over the lead role from John Nettles in 2011.

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The show is known for its stellar guest stars, many of whom achieved greater fame after being cast as a murder victim or murderer in one of Midsomer's sprawling, hour-long mysteries. In other cases, the guest star is already famous and serves as a familiar face for viewers to spot. Below are 10 actors and actresses you probably had no idea were on Midsomer Murders.

10 Lesley Manville

Lesley Manville is best known for her role as the conniving madam Lydia Quigley on HarlotsShe also appeared in the Midsomer Murders episode "Fit For Murder," which is notable for being John Nettles's final episode before handing over the reins as DCI Barnaby to Neil Dudgeon.

Manville plays Phoebe Archibald, the co-owner of the health club and spa where Joyce Barnaby takes her husband for some much-needed rest and relaxation. Of course, this being Midsomer Murders, it wasn't long before the first body showed up - in the sensory deprivation tank of all places - and Archibald became involved in the ensuing investigation.

9 James Callis

James Callis made a name for himself as Dr. Gaius Baltar in the critically acclaimed sci-fi drama Battlestar Galactica. He also appeared in the Midsomer Murders episode "The Dark Rider," where he played identical twin brothers Toby and Julian DeQuetteville. Callis shows off his acting chops in this episode as the two brothers have completely different personalities.

Whereas Toby is meek and gentle, Julian is dominant and assertive, often to the point of bullying his brother. They both come under suspicion in DCI Barnaby and DS Jones's investigation when a series of murders perpetrated by a mysterious headless horseman rocks the family estate.

8 Sally Phillips

Known for her role as Finnish prime minister Minna Hakkinen on the HBO comedy Veep, Sally Phillips also appeared in the Midsomer Murders episode "The Village That Rose From The Dead." She played Lucy Keswick, a property developer with a stake in Little Auburn, a village that had been abandoned since World War II.

With a plan to develop the village into a luxury retreat, she was at odds with other Midsomer residents who wanted to build an eco-friendly village or preserve Little Auburn as a living museum. The stakes for the competing proposals became even higher when a local man is found crushed to death under a tank outside the village.

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7 Harriet Walter

Harriet Walter was most recently seen as Lady Caroline Collingwood in the HBO hit Succession. She also had minor roles as Clementine Churchill in The Crown and Lady Shackleton in Downton Abbey. She has appeared in two episodes of Midsomer Murders: "Orchid Fatalis" and "Death And The Divas."

In "Orchid Fatalis," she played an eccentric professor and botanist; in "Death And The Divas," she played a famous actress whose star has faded due to her sister's interference. The diversity of roles Walter has had in popular and critically acclaimed historical and contemporary dramas is certainly a testament to her skill as an actress.

6 Samantha Bond

Best known for her role as Miss Moneypenny in the James Bond films starring Pierce Brosnan, Samantha Bond has also appeared in Downton Abbey as Lady Rosamund Painswick, sister of the Earl of Grantham and mentor to Lady Mary and Lady Edith. She is also in three episodes of Midsomer Murders: "Destroying Angel," "Shot At Dawn," and "Death In The Slow Lane."

As with Harriet Walter and other actors and actresses who have appeared in multiple episodes of this popular detective show, Bond played completely different characters in all three episodes, keeping the audience on its toes and demonstrating her versatile acting chops.

5 Jim Carter

Downton Abbey fans may know Jim Carter as the traditional and severe butler Mr. Carson, a role that earned him four Emmy nominations for Outstanding Supporting Actor in a Drama Series between 2012 and 2015, and which he recently reprised for the Downton Abbey movie.

Years before he landed the career-making role, Carter also had a small part in the Midsomer Murders episode "The Fisher King" as Nathan Green, riverbank keeper, and father of murder suspect Harry Green. DCI Tom Barnaby and DS Dan Scott questioned Mr. Green about the death of Gareth Heldman, who was murdered by an ancient Celtic spear under suspicious circumstances.

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4 Tobias Menzies

"Judgment Day" is a classic Midsomer Murders episode famous for Orlando Bloom's pre-Lord of the Rings appearance as murder victim Peter Drinkwater. Many viewers might not realize that Tobias Menzies also appeared in the same episode as Jack Dorset, Drinkwater's friend, and accomplice.

Son of the village butcher, Dorset is questioned by DCI Tom Barnaby and DS Gavin Troy about Drinkwater's death and the string of seemingly unrelated burglaries in the area. Menzies went on to have major roles in Outlander, Rome, and Game Of Thrones, and he is set to portray Prince Philip in seasons 3 and 4 of The Crown!

3 Sam Heughan

Like Tobias Menzies, Outlander star Sam Heughan appeared in Midsomer Murders before making it big. He played Ian King, son of the late factory owner in "The King's Crystal." Ian is initially reluctant to take over the family business after his father dies and his mother remarries.

The episode weaves an intricate mystery involving the future of the glassware factory, outsourcing jobs to China, and Masonic rituals. Ever the heartthrob, Heughan's character is also part of a love triangle with his best friend and the daughter of the factory accountant who also happens to be another suspect in DCI Tom Barnaby and DS Ben Jones's investigation.

2 Clarke Peters

It may be a little surprising to see an American actor on Midsomer Murders, but given the number of Brits (Idris Elba and Dominic West in particular) who mastered their American accent to play Baltimore natives in The Wire, there's no reason why their co-star and honorary Brit Clarke Peters wouldn't take a role across the pond.

Known for his role as Detective Lester Freamon on The Wire, Clarke appeared in "The Ballad Of Midsomer County" as a pub landlord with an agenda to keep a local folk festival in Midsomer County for his business instead of moving it to London.

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1 Kevin Doyle and Raquel Cassidy

Molesley and Baxter were one of the most adorable pairings on Downton Abbey that somehow never became canon -- so it only seemed appropriate to include them in the same entry on this list. Raquel Cassidy played James Callis's onscreen wife in "The Dark Rider," while Kevin Doyle appeared as Ferdy Villiers, a local man whose suicide continues to haunt his family nine years after the fact in "Ghosts of Christmas Past."

Doyle also appeared in a more recent Midsomer Murders episode as a pub owner under investigation in "The Oblong Murders." Both Doyle and Cassidy were hardly recognizable as their Downton Abbey characters in these guest appearances.

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