The show is based on Caroline Graham's Chief Inspector Barnaby book series, originally adapted by Anthony Horowitz.
Carla Constanza, a Brazilian actress and advertising face of Monarch Tobacco, is found strangled with a necktie in Raven’s Wood.
As residents of Midsomer Mallow prepare for the 'Perfect English Village' competition, local thief and lothario Peter Drinkwater (Orlando Bloom) is stabbed with a pitchfork at the abandoned Windy Whistle Farm.
He begins his last case in Midsomer, investigating the murder of a teenager, Simon Mayfield (played by Henry Cavill), who had been shot with a gun that he and his friends had been using the previous night.
The two detectives discover their cases are linked, and uncover a web of lies, affairs, and domestic arguments alongside a mysterious recluse with a hidden past.
DCI Barnaby and Acting DC Ben Jones enter a world where crooked estate agents, property developers, and eccentric villagers all seem to be withholding information.
With DC Jones awaiting news of his promotion to Detective Sergeant, they find themselves reinvestigating and uncover new evidence that puts the case in a very different light.
The Midsomer Rocks festival is due to take place and music fans descend on neighbouring fields to enjoy the fiesta.
Shortly afterwards, a body is found in a shallow grave, giving Barnaby and Jones an accurate description of one of the "missing" persons.
With a break-in at the local museum, a cricket match, rivalries, and secret loves, other murders take place and Barnaby soon suspects the killing of Larkin has links to events in Berlin during the Cold War.
During a council meeting, Causton Mayor Dave Hicks announces plans for a Chamber of Commerce reunion with its counterpart in Brighton.
A quiet spa weekend at Swavely Manor proves far from relaxing when Tom and Joyce arrive and a female client is found murdered in the flotation chamber.
Years earlier, the body of a renowned racing car driver had been found at the prestigious Darnley Park Girls School, apparently having committed suicide with a revolver.
The lives of elderly eccentrics William and Mary Bingham come under police investigation when a social services inspector is found dead in the river, apparently from a canoeing accident.
Lucy Oliver, daughter to friends of George Bullard, disappears from a manor house being used by the Oblong Foundation, a New Age cult organisation.
Farmer Alex Preston's dead body is found in the centre of the ancient Crowcall stone circle days before the spring equinox.
Early evidence points to a community of New Dawn Druids, who had been angered over Preston's plans to plough the meadow and make the sacred place inaccessible.
But when one of the druids is also murdered, Barnaby realises that more complex motives are involved, and his suspicions turn in a direction that threatens to create a serious rift between him and Jones.
Maps that reveal the location of a hidden Anglo Saxon treasure, along with a more modern valuable painting, provide the clues that lead to a very manipulative killer.
When Eve Lomax, a film journalist writing a book about 1960s horror actress Stella Harris, is found dead in Midsomer Langley, it appears her neck was punctured by a vampire.
When Debbie Moffett is lured to the caves and is subsequently bludgeoned by a wheel of cheese, it leads the detectives to investigate both the secret, controversial plans to modernize the dairy and the private lives of the parents of children at the local preparatory school in the same village.
When more people are killed, long-held secrets about the dairy, school, and villagers are revealed and play a key role in catching the killer.
The Manor has a haunted reputation involving stories of a blacksmith's daughter, and the voice of a young girl on a tape recording from the night of the murder adds to the mystery.
When wealthy landowner Gregory Lancaster's body goes missing on the night of his death, it starts a series of mysterious events in the village of Little Malton.
After the son of an equestrian centre owner is found trampled by his own horse, the detectives have to look into a case with much complexity that has its roots in the past, in order to solve an investigation where nothing is what it seems.
When Roderick Craven, the head of the judging panel that will decide Little Auburn's redevelopment and his brother Milo are also found murdered, an unexpected new beneficiary of the rights to the village comes to light.
When star cricketer Leo Henderson is murdered in the club's training shed, DCI Barnaby and DS Winter eventually find out that this case is about gambling, bribery, burglary, and the disappearance of a local woman.
Barnaby is surprised when he sees Morris for the first time – his former DS Ben Jones, now promoted to DI in Brighton, and working undercover.
At the end of the Thassington classical music festival in the village church, the winner of the Falconer Award is announced as Jacob Wheeler.
Adam Asoba is found murdered, having been boiled to death in one of the vats at the newly opened brewery of the famously cursed abbey in Midsomer.