ITV News correspondent Paul Davies explores the theories surrounding the death of MI6 code-breaker Gareth Williams.
Please do not attempt to recreate the demonstration contained in the video.
Mr Williams' decomposing naked body was discovered padlocked inside a holdall in his flat in August 2010. Today coroner Dr Fiona Wilcox delivered a narrative verdict, stating it is "very unlikely" the mystery will ever be explained.
On the balance of probabilities, the Coroner agrees with Mr Williams' family that Gareth was unlawfully killed - though that's not the actual verdict.
Dr Fiona Wilcox thanks DCI Jackie Sebire, who is leading police inquiry, and gives her sympathies to Gareth's family.
Coroner Dr Fiona Wilcox says she's satisfied the bag was placed in bath by a third party, probably to conceal the decay of body and leakage.
She adds it's "beyond belief" Gareth could have arranged the lock and zips so neatly from the inside.
The coroner says Gareth Williams' death was caused by an "unnatural cause" but she added that she could not be "satisfied so that I'm sure that he was ... unlawfully killed".
Coroner suggests inaccurate reporting of Gareth William's personal life was attempt by a third party to manipulate perceptions of the case.
The coroner says it is "highly unlikely" Gareth got into the red bag alone in bath - there should have been foot and fingerprints in vicinity.
Coroner Dr Fiona Wilcox revealed the extent of the police investigation into the death of MI6 agent Gareth Williams, while delivering a narrative verdict.
- Police interviewed more than 200 witnesses.
- 110 CCTV clips were collected.
- 300 house to house inquiries were conducted.
During the narrative verdict, Coroner Dr Fiona Wilcox says two keys to the padlock were found under Gareth's body, two others were locked in a cash box
She adds it is "highly significant" none of Gareth's fingerprints were found on the tiles or the shower screen near the bag.
Coroner Dr Fiona Wilcox says Gareth looked "peaceful" in the bag, which was undamaged and he seems not to have tried to get out.
The Coroner says "many agencies" fell short of the required standard in handling of this case - police, MI6, LGC forensics and the Coroner's office.