Murder Island: what is channel 4 TV show written by Ian Rankin about, who is in cast, and when does it start?

The murder mystery plot has been written by award winning Scottish author Iain Rankin

Inspector Rebus writer Ian Rankin has written some of the best crime fiction of the past three decades.

Now, his murder mystery novels have been adapted for screen, in a new contestant show for Channel 4, in which regular people become detectives in a murder case set on the Isle of Gigha, Scotland.

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The innovative format will combine real life investigative skills with expert knowledge to solve a fictional crime.

The winners must present their case to one of Scotland’s leading lawyers and convince them of their findings, in a bid to win £50,000.

So, what is the plot of the show and who are the teams of detectives? This is what you need to know.

What is Murder Island about?

According to ITV, the show is based on the fictional island of Hirsa, less than 20 miles off the west coast of Scotland.

The series was actually filmed on the remote Scottish island of Girgha.

When a body is discovered on the remote, tranquil island, a murder investigation gets underway.

The murder mystery has been written by Rankin, eight contestants working in groups of two will need to unpick the clues to determine the suspect, method and motive of the crime.

Th island of Gigha was used to film the murder mystery (Picture: Getty)

The investigation is overseen by some of the country’s finest real detectives, who will work

with the same information as the amateur detectives and will bring their own experience

to bear as they judge each team.

The teams have eight days to catch the killer, sifting through evidence, examining pathology and forensic reports and interviewing witnesses and suspects.

Once they have concluded their investigation, they must build a strong enough case to satisfy one of Scotland’s leading lawyers, then they could earn a £50,000 reward.

Who are the experts on Murder Island?

The murder case will be overlooked by three experts, a former Met Superintendent and a  retired DCI and DI of a major crime unit.

So, who are they?

Parm Sandhu

Former Chief Superintendent at the Met, Parm Sandhu was the highest ranking Asian

female police officer in the London force.

Parm is a trained Senior Investigation Officer (SIO) on murder investigations who grew up in Handsworth, Birmingham and witnessed the culture clash within her neighbourhood.

She is the only non-white female to have been promoted through the ranks from constable to chief superintendent in the Met’s 192-year history, prior to retiring in 2019.

Throughout her career, she also led national counter terrorism teams, Fraud and Cyber investigations.

Aged 15, she was forced into an arranged marriage and aged 21, she left the marriage with her baby son and only the clothes on her back.

Having left her husband, she moved to London and finally got on her feet, joining the Met at the age of 25.

Simon Harding

Harding is a retired Detective Chief Inspector, serving The Met Specialist Crime Unit (Homicide).

He won National SIO of the year award in 2020 and has been a homicide SIO for the past 4 years. Throughout his career, he dealt with over 80 murders and has worked for the past 27 years as a detective specialising in murder and terrorism.

The 6ft 4 detective is a Subject Matter Expert in homicide (SME) which means he can get a call from any force regarding guidance on a homicide investigation.

He retired from his role in the Met earlier this year.

Graham ‘Maca’ McMillan

Retired Detective Inspector McMillan worked on the Serious and Organised Crime Unit in the Bedfordshire Police force for nearly 25 years.

Prior to his police career, he spent eight years in the Army and during his investigative role he worked on over 100 murders.

He is a Tier 5 Level Interviewer, and a hostage and crisis police negotiator.

He has significant experience in senior strategic investigative management roles within both Major Crime and Serious and Organised Crime.

He has been awarded a number of Chief Constable and Head of Department Commendations and his work has been featured in the television documentary

24 Hours in Police Custody.

McMillan also helps author Susie Steiner with her crime writing, advising on plot. Maca is a keen football player and supports Everton.

Who are the contestants?

Sarah and Richmond


(Picture: Channel 4)

28 year old Sarah and Richmond, 30, are fiances and parents to their three-year-old daughter.

Sarah studied criminology and sociology at university, a course she loved, but once she graduated followed a different path and now works in recruitment. An ex pro-footballer,

Richmond became unemployed after a health scare and now volunteers as a football coach for 12 children in his local area.

The pair claim they have what it takes to be successful murder detectives, Richmond claims he has a great judge of character and Sarah has the prior knowledge from her degree. The couple have also admitted to being fiercely competitive.

Andrew and Nick

London and Edinburgh

(Picture: Channel 4)

Brothers-in-law Andrew, 28 and 33-year-old Nick grew up together as their parents are friends and Nick is now married to Andrew’s sister.

Andrew works as a Marketing Manager for a craft beer company and former Captain in the British Army Nick works as a Digital Director in tech.

They believe they have what it takes to solve the case, Andrew comes from a long line of serving police officers and his father would often share fascinating insights and stories.

Andrew hopes to prove to his father that he too could solve a murder, Nick hopes to apply his analytical thinking and his experience under pressure in an intense environment to solve the case.

Chrissie and Caroline (64)


(Picture: Channel 4)

Next Door Neighbours Chrissie and Caroline first met at a local amateur dramatics club, but moved in through the wall from one another five years ago.

Former teacher Chrissie, 77, and best friend Caroline, 64, want to fly the flag for mature, strong women and give the younger generation a run for their money.

They think their life experience combined with their love of detective novels and TV drama will be invaluable on the island.

The duo believe their opposite natures will stand them in good stead, as Caroline is inquisitive and hands on, whereas Chrissie prefers to observe and check all the facts before drawing conclusions.

Dot and Rox


(Picture: Channel 4)

This pair, both in their early twenties, met while working in a pub together five years ago and have been inseparable since.

Dot, 22, and 24-year-old Rox love investigating and hope taking part in the show could inspire them to change careers.

Dot works in the pub she lives above and she is used to customers confiding in her, she has recently completed a Private Investigation course and wants to

stop pulling pints and start picking criminals.

Rox works for a property lawyer firm and is about to start an Open University Criminology course to explore if detective work is her next calling.

When does Murder Island start on Channel 4?

Murder Island begins Tuesday 5 October at 9:30pm on Channel 4 and All 4.