Sergeants · Tom Barnaby
Gavin Troy
DS Gavin Troy is a detective sergeant and later inspector, played by Daniel Casey in Series 1–7 · guest in Series 11.
Ambitious, impatient and famously hazardous behind the wheel. Troy's blunt instincts give Tom's measured questioning its foundational comic contrast.
Who they are
Gavin Troy is the original Causton sergeant, played by Daniel Casey across Series 1–7, from The Killings at Badger’s Drift in 1997 through his final regular case, The Green Man, in 2003. He later returns as a guest in Series 11’s Blood Wedding. Troy begins as Detective Sergeant beside Tom Barnaby and later becomes an inspector. That promotion gives the character a visible professional trajectory, rather than leaving him fixed in the junior position in which the partnership starts. He is one of the two central investigators in the early stories, so his reactions help set the audience’s first expectations of how a Midsomer inquiry unfolds.
Troy’s early characterization is more direct and impatient than Tom’s. The difference is played for humour—especially around his driving and quick conclusions—but it also creates a working contrast. Troy is willing to act on an immediate impression, and Tom is more likely to ask what that impression leaves out. The show’s village settings often encourage outsiders to form an opinion quickly; Troy’s learning curve lets the series test that impulse in a character who is still becoming an experienced detective. His development does not erase his energy. Instead, the role grows from a younger officer beside Barnaby into a colleague whose own advancement is part of the story.
Working relationships
Tom is Troy’s defining professional relationship. Their first partnership gives the series a reliable two-person rhythm: Tom asks, listens and revisits, while Troy often supplies a quicker response to a suspect or an unusual situation. It would be misleading to reduce Troy to comic relief, because he is part of the investigative work and grows in rank as he gains experience. The humour comes from friction between approaches, not from the idea that he cannot do the job. Across cases, the two share enough familiarity to disagree without the partnership collapsing.
George Bullard is a recurring professional presence from the same early period. His pathology work provides a scientific counterpoint to Tom and Troy’s interviews and field inquiries. Joyce and Cully connect Troy to the Barnaby household in a different way: they are part of his employer’s family circle, not members of the police team. The distinction keeps his social interactions separate from investigative authority. When Troy returns in Blood Wedding, he is no longer simply the sergeant Tom once supervised. His later rank and his reunion with Tom show how time and career movement have changed the relationship, even as the old familiarity remains recognizable.
Key episodes
The Killings at Badger’s Drift. The pilot introduces Troy as Tom’s sergeant in an inquiry that establishes the series’ village-mystery pattern.
Written in Blood. A writers’ circle visit places the team among literary rivalries and a community with carefully managed secrets.
Death in Disguise. A death at a New Age commune sends the detectives into a secluded household with competing identities.
Blue Herrings. Tom’s aunt suspects a pattern at her nursing home, taking the partners into a quieter institutional setting.
Murder on St Malley’s Day. A prestigious school and its secret traditions place a new institution at the centre of an inquiry.
The Green Man. A canal tunnel collapse exposes remains and gives Troy his final regular investigation beside Tom.
Blood Wedding. Troy returns at a wedding weekend, revisiting Tom as a more senior officer and old colleague.
How they change
Troy changes from a young, fast-moving sergeant into an officer who can carry a different rank and identity beyond the original partnership. The early cases give him room to react before he has the knowledge Tom has accumulated. Over time the audience sees him become familiar with the people, routines and oddities of Causton. His advancement into inspector is part of the character’s endpoint, not a footnote: it signals that his path continues outside the immediate work of Tom’s team. The show never needs to turn him into a different person to show growth; more experience sits beside the impatience and warmth that first defined him.
The Green Man is Troy’s final regular case, and Blood Wedding later brings him back for a guest appearance. This lets him leave the weekly team without vanishing from the series world. His return measures the change: he meets Tom as a colleague from a former phase of both careers, not as a junior who needs correction. His arrival is The Killings at Badger’s Drift, the 1997 pilot. His regular departure is The Green Man, Series 7 episode 1; Blood Wedding is the later return. The arc shows a beginning, a professional advancement and a reunion, while Troy retains the qualities associated with the original partnership. The return lets the show acknowledge a colleague’s continuing career without reopening their old daily working arrangement. His change in rank also reframes the humour of their old exchanges as mutual familiarity.
Episode-by-episode
Cases that chart the character
Series 1 · 1997 · Badger's Drift
The Killings at Badger's Drift
Read the episode premise →The feature-length case that established the entire Midsomer formula.
DCI Tom Barnaby · DS Gavin TroySeries 1 · 1998 · Midsomer Worthy
Written in Blood
Read the episode premise →A particularly sharp collision of village insecurity and literary vanity.
DCI Tom Barnaby · DS Gavin TroySeries 1 · 1998 · Ferne Basset
Death of a Hollow Man
Read the episode premise →Midsomer's love affair with catastrophically competitive societies begins early.
DCI Tom Barnaby · DS Gavin TroySeries 1 · 1998 · Morton Fendle
Faithful Unto Death
Read the episode premise →An early case that keeps changing shape as Barnaby tests every convenient explanation.
DCI Tom Barnaby · DS Gavin TroySeries 1 · 1998 · Lodge of the Golden Windhorse
Death in Disguise
Read the episode premise →The first series closes by putting its most traditional detective inside its least traditional household.
DCI Tom Barnaby · DS Gavin TroySeries 2 · 1999 · Badger's Drift
Death's Shadow
Read the episode premise →One of the early era's darkest and most highly regarded mysteries.
DCI Tom Barnaby · DS Gavin TroySeries 2 · 1999 · Midsomer Worthy
Strangler's Wood
Read the episode premise →A sombre early mystery that places an old serial-killer fear beside corporate and family pressure.
DCI Tom Barnaby · DS Gavin TroySeries 2 · 1999 · Fletcher's Cross
Dead Man's Eleven
Read the episode premise →Cricket, class and a formidable guest performance make this a distilled piece of early Midsomer.
DCI Tom Barnaby · DS Gavin TroySeries 2 · 1999 · Martyr Warren
Blood Will Out
Read the episode premise →The case uses an apparent clash between villagers and newcomers to expose violence already rooted inside one household.
DCI Tom Barnaby · DS Gavin TroySeries 3 · 1999 · Upper Marshwood
Death of a Stranger
Read the episode premise →Barnaby begins the series by challenging a senior officer's tidy conclusion and following the people whom the first inquiry overlooked.
DCI Tom Barnaby · DS Gavin TroySeries 3 · 2000 · Aspern Tallow
Blue Herrings
Read the episode premise →A gentler, character-led case in which older residents prove sharper than their carers expect.
DCI Tom Barnaby · DS Gavin TroySeries 3 · 2000 · Midsomer Mallow
Judgement Day
Read the episode premise →Few episodes express the central joke of Midsomer more neatly: perfect hedges, disastrous neighbours.
DCI Tom Barnaby · DS Gavin TroySeries 3 · 2000 · Aspern Tallow
Beyond the Grave
Read the episode premise →The supernatural dressing is unusually persuasive, but every apparition also changes who controls the village's version of history.
DCI Tom Barnaby · DS Gavin TroySeries 4 · 2000 · Midsomer Deverell
Garden of Death
Read the episode premise →A lavishly tangled family case with classic country-house scenery.
DCI Tom Barnaby · DS Gavin TroySeries 4 · 2001 · Midsomer Magna
Destroying Angel
Read the episode premise →A celebrated revenge story whose eccentric methods never overwhelm its emotional logic.
DCI Tom Barnaby · DS Gavin TroySeries 4 · 2001 · Midsomer Parva
The Electric Vendetta
Read the episode premise →Flying-saucer talk supplies the spectacle while the real mystery travels backwards through two families and an old airfield story.
DCI Tom Barnaby · DS Gavin TroySeries 4 · 2001 · Newton Magna
Who Killed Cock Robin?
Read the episode premise →The opening question—where did the man hit by the car go?—keeps changing as Barnaby establishes which disappearance he is actually solving.
DCI Tom Barnaby · DS Gavin TroySeries 4 · 2001 · Goodman's Land
Dark Autumn
Read the episode premise →Its autumnal atmosphere and ordinary village rounds create one of the show's most quietly unsettling cases.
DCI Tom Barnaby · DS Gavin TroySeries 4 · 2001 · Midsomer Malham
Tainted Fruit
Read the episode premise →The victim has offended almost everyone, but the case is less about popularity than the power to control land, work and private lives.
DCI Tom Barnaby · DS Gavin TroySeries 5 · 2002 · Midsomer Market
Market for Murder
Read the episode premise →A smart ensemble mystery about financial independence, friendship and the cost of being underestimated.
DCI Tom Barnaby · DS Gavin TroySeries 5 · 2002 · Midsomer Worthy
A Worm in the Bud
Read the episode premise →Children's evidence overturns the first reading of the death and gives the investigation an unusually clear moral centre.
DCI Tom Barnaby · DS Gavin TroySeries 5 · 2002 · Midsomer Wellow
Ring Out Your Dead
Read the episode premise →Its bells provide both atmosphere and structure for a particularly English procession of grievances.
DCI Tom Barnaby · DS Gavin TroySeries 5 · 2002 · Devington
Murder on St Malley's Day
Read the episode premise →A pointed mystery about institutions that protect themselves.
DCI Tom Barnaby · DS Gavin TroySeries 6 · 2003 · Midsomer Malham
A Talent for Life
Read the episode premise →Memorable for Honor Blackman's commanding guest performance.
DCI Tom Barnaby · DS Gavin TroySeries 6 · 2003 · Midsomer Worthy
Death and Dreams
Read the episode premise →A disturbing late-Troy case that pushes the series closer to psychological horror.
DCI Tom Barnaby · DS Gavin TroySeries 6 · 2003 · Midsomer Florey
Painted in Blood
Read the episode premise →Barnaby being formally removed from the case creates a playful contest between official secrecy and his refusal to stop noticing things.
DCI Tom Barnaby · DS Gavin TroySeries 6 · 2003 · Upper and Lower Warden
A Tale of Two Hamlets
Read the episode premise →The episode turns a centuries-old village feud into both local folklore and a profitable family entertainment business.
DCI Tom Barnaby · DS Gavin TroySeries 6 · 2003 · Midsomer Magna
Birds of Prey
Read the episode premise →Troy's wildlife case and Barnaby's murder inquiry begin on separate tracks before the same trade in rarity and credibility joins them.
DCI Tom Barnaby · DS Gavin TroySeries 7 · 2003 · Midsomer Worthy
The Green Man
Read the episode premise →A melancholy mystery and Gavin Troy's final regular case.
DCI Tom Barnaby · DS Gavin Troy