What's the story?

Murder Island.

I'll need more information.

It is a new six-part Channel 4 series based around a murder mystery plot.

Written and developed by none other than Ian Rankin, the show is filmed on Gigha, aka the fictional Hirsa, where the 173-strong island community is served by one pub, a single shop and a primary school.

However, the tranquillity of life on Hirsa has been shattered. A body has been discovered and a murder investigation is under way.

HeraldScotland: Murder Island is the work of Rebus creator and crime writer Ian RankinMurder Island is the work of Rebus creator and crime writer Ian Rankin

I'm confused. What genre is this?

Glad you asked. Interestingly, the format blends factual, drama, reality TV and competition elements into one programme.

How does that work?

The contestants – split into four two-person teams – take on the role of amateur detectives and lead their own investigations.

Each duo has eight days to catch the killer, sifting through evidence, examining pathology and forensic reports, as well as interviewing witnesses and suspects.

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They must solve the crime and build a watertight case that can stand up in court, all under the watchful eyes of real-life senior investigating officers and leading lawyers.

What's the object?

Money. The winning team will claim a £50,000 prize.

HeraldScotland: Graham McMillan and Simon Harding are among the crime experts on the new Channel 4 series Murder Island. Picture: STV Studios/Channel 4Graham McMillan and Simon Harding are among the crime experts on the new Channel 4 series Murder Island. Picture: STV Studios/Channel 4

How is Ian Rankin involved?

The Rebus creator and award-winning crime writer has devised the twisting murder mystery.

When can I watch?

Murder Island begins on Channel 4, Tuesday, 9.30pm.