When 31-year-old nurse Susan Annis was found dead whilst on a course at the Royal Brompton Hospital, police attributed her death to a heart condition. But three years later, a sexual assault in a hospital's emergency department led detectives to her killer.

Former detective Colin Sutton revisits the locations of various important cases and reveals how they were solved.

Former detective Colin Sutton details how he and his team worked on the cold-case investigation of Catherine Corridan's disappearance alongside other high-profile cases.

A look at the investigation into the attempted murders of Gary Mullins and Colin Meek during an armed robbery in 1994.

Sutton looks back at the murder of an 18-year-old and how the young killers who took turns to kick his head and body were caught

Colin Sutton revisits the case of The Night Stalker - serial rapist Delroy Grant, and reveals how he brought his 17-year reign of terror to an end.

Sutton revisits the murders of marsha mcdonnell,amelie delagrange and milly dowler,and how their killer,levi bellfield,was caught

Harvey Nichols beauty consultant Clare Bernal and security guard Michael Pech had only been on three dates when he began a sustained campaign of stalking against her. Eventually, she reported his behaviour to the police - he had been following her, texting her up to 50 times a day, threatening her - and he was arrested. On September 15th, 2005, Pech was out on bail awaiting sentencing for harassment when he walked into Harvey Nichols and shot the 22-year-old once in the back of the head then three times in the face. She died instantly and he then turned the gun on himself.

The Murder of Sinead Healy: True-crime series follows former detective Colin Sutton as he revisits the locations of various important cases and reveals how they were.

Former detective Colin Sutton revisits the locations of various important cases and reveals how they were solved.

The Murders of Nisha Sheth, Brian Cherry and Richard Loudwell - The Peter Bryan Case: Ex-detective Colin Sutton revisits the locations of important cases.

True-crime series following ex-detective Colin Sutton as he revisits important cases and reveals how they were solved.

The killings of of James Attfield and Nahid Almanea in 2014 15-year-old Essex boy James Fairweather. Was the teenager's Ripper obsession to blame or was their more to his story?

After being picked up by NHS worker Duncan Bone at King's Cross in 1992, Karl Warne and Colin Lockett would murder their host at his flat.

True-crime series following ex-detective Colin Sutton as he revisits important cases and reveals how they were solved.

Colin Sutton and team make a horrific discovery when 43-year-old Eastenders actress Sian Blake and her two children are reported missing in 2015.

Colin Sutton recounts his investigation into an attack against an elderly couple, who were stabbed in their home by a man they knew well.

Ex-detective Colin Sutton revisits the murder of Ronnie Cook, killed by his lover who was later dubbed 'the Black Widow'

An occult-obsessed man gets jail time after viciously stabbing his friend to death. Upon his release, he strikes again.

Thomas Hughes murdered pregnant, 22-year-old Krystal Hart with two gunshots to the head on the doorstep of her home in a ruthless execution style murder. Following a long-running dispute between Hart and 'neighbour from hell' Angie Brewer, Hughes took it upon himself to carry out the revenge attack after becoming besotted with Brewer. In a surprising twist, there were CCTV cameras placed above the door to discourage and monitor the feud which Thomas Hughes either ignored or knew nothing of which would help to secure a conviction during the trial. But first, the police had to track Hughes down.