How I Caught The Killer

Masud - Unrequited Love: After ending her relationship, 15-year-old Maleha Masud pays the ultimate price when her ex-boyfriend starts a lethal blaze at her home. (S3, ep 5)

Sievers - A Murder for Hire: Documentary lifting the lid on police investigations into some of the most incredible murder cases in criminal history. (S3, ep 6)

Sievers - A Murder for Hire: Documentary lifting the lid on police investigations into some of the most incredible murder cases in criminal history. (S3, ep 6)

Letter From the Grave - Mark Jensen: When Julie Jensen is found dead, police suspect her husband Mark of murder - despite the seemingly happy family life. (S4, ep 7)

Letter From the Grave - Mark Jensen: When Julie Jensen is found dead, police suspect her husband Mark of murder - despite the seemingly happy family life. (S4, ep 7)

Killer Women - Kaitlin Armstrong - Malicious Intent: When elite racer Anna Wilson was shot and killed, police launched a manhunt to Costa Rica in search of Kaitlin Armstrong. (S4, ep 8)

Killer Women - Kaitlin Armstrong - Malicious Intent: When elite racer Anna Wilson was shot and killed, police launched a manhunt to Costa Rica in search of Kaitlin Armstrong. (S4, ep 8)

Love Always in God - Benjamin Laing: Six days after Matthew Manwaring and his daughter Alison vanish, police uncover a grisly scene at Benjamin Laing's home. (S4, ep 9)

Love Always in God - Benjamin Laing: Six days after Matthew Manwaring and his daughter Alison vanish, police uncover a grisly scene at Benjamin Laing's home. (S4, ep 9)

A Cold-Hearted Killing - Douglas Ward: When young kickboxing champion Niall Dorr was beaten to death in Dundalk, CCTV helped detectives convict his killer. (S4, ep 10)

A Cold-Hearted Killing - Douglas Ward: When young kickboxing champion Niall Dorr was beaten to death in Dundalk, CCTV helped detectives convict his killer. (S4, ep 10)

Traces of DNA: In 1986, Detective David Baker became the first person to use DNA profiling in a criminal investigation, when looking for the killer of two young girls.

Traces of DNA: In 1986, Detective David Baker became the first person to use DNA profiling in a criminal investigation, when looking for the killer of two young girls.