1. Susan Warne

When seemingly healthy John Proctor was found dead at home, police were stumped. But, a woman in his family was hiding a dark secret that lead to his death.

3. Hannegret Donnelly

Christopher Donnelly was found battered with 78 visible injuries in Aylesbury, Buckinghamshire. His wife, Hannegret, had been abusing him at home for years.

4. Singh

A classic love triangle that lasted 16 years led to a shocking murder by Lakhvir Singh in 2009. Her method of killing gave her the nickname 'The Curry Killer'.

5. Sabrina Kouider

The ex-girlfriend of Boyzone member Mark Walton was arrested for the murder of French nanny, Sophie Lionnet. Why did Sabrina Kouider brutally kill this woman?

6. Mahmuda Khatun

28-year-old Mahmuda Khatan stabbed her husband of only one month on his birthday. Police detectives, experts and acquaintances discuss why she murdered him.

7. Zatoon Bibi

When Tanveer Iqbal’s body was discovered in the boot of his car, Zatoon Bibi, her husband and 15-year-old son were arrested for his murder. Why did this family kill?

8. Virginia Vertetis

When Patrick Gilhuley was shot dead by his partner in 2014, she claimed it was self-defence, but her ex-husbands provided evidence of her violent past.

9. Kelly Cochran

Kelly and Jason Cochran formed a killer husband and wife team – but then she turned on him. How many lives did she take before she was caught?