It's a case that has perplexed the general public as well as authorities for over 30 years. Suzy Lamplugh, an estate agent from London, went missing in July 1986 from her place of work, and has since never been found.
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On Wednesday evening, Channel 5 aired an investigative documentary exploring the case of Suzy, hearing from key people involved in the investigation including former senior detectives who worked on the case and Suzy's family members.
WATCH: Channel 5 air true-crime documentary The Vanishing of Suzy Lamplugh
But it seems that while many were fascinated by the show, viewers were particularly "horrified" and "devastated" at the revelations that emerged in the one-off programme.
Plenty took to social media to give their verdict on the true-crime documentary. "It is devastating her parents never saw justice or found Suzy's body. Her legacy was the charity to help keep women safe @live_life_safe set up by her inspiring mum Diana Lamplugh", wrote one viewer.
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Suzy went missing in 1986
Another tweeted: "Of criminal cases, #SuzyLamplugh has remained with me since childhood, along with that of #StephanieSlater. When I watch documentaries now about #Suzy, I can't begin to imagine how devastating her disappearance must have been on her family, especially as it has yet to be solved."
There were other aspects within the programme that audiences picked up on, including the revelation that an eye-witness, now deceased, reported to the Met police a number of times that he had in fact seen a person throwing a large suitcase into the Grand Union canal. The eye-witness had seen the prime suspect at the time, John Cannan, on TV and recognised him before reporting it to the police, but his account was not pursued.
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The 25-year-old estate agent's home in Fulham
Another viewer wrote on Twitter: "When will this put right? When will that canal be properly searched? No excuse will suffice. No apology will be good enough if the #suzylamplugh doc was correct tonight. Shameful negligence. #Suzy." Another commented: "#SuzyLamplugh documentary very affecting. Hundreds of female bodies lying in morgues and not getting identified, horrific."
John was in fact arrested in relation to another crime with similar circumstances to Suzy, and remains in prison to this day, but he was not directly convicted for the crimes against the 25-year-old estate agent, who was declared dead in 1994.
John Cannan was a prime suspect in Suzy's case, and is currently serving a sentence for other crimes
The Crown Prosecution Service at the time ruled there was not enough concrete forensic evidence to convict John, despite other facets implementing his guilt – including a testimony from his ex-partner. John is currently serving three life sentences for the murder of Shirley Banks in October 1987, attempted kidnapping of Julia Holman the night before Shirley's death, and the sexual assault of a woman in 1986. Cannan is serving his sentence at HMP Full Sutton in York, and will be eligible for parole in 2023.
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