The agent's body was found in a padlocked bag

 On August 23, 2010, police were investigating the fate of a resident in an exclusive tenement building at 36 Alderney Street in London. Officers forced their way inside. The apartment was spotlessly clean, with phones and laptops neatly stacked on the table. However, in the bathroom adjacent to the bedroom, a gruesome discovery was made.

A red The North Face duffel bag was leaking liquid in the bathtub. The bag was closed, its two zippers locked together and secured with a padlock. Inside was the naked, decomposing body of a 31-year-old man in a fetal position. The keys to the padlock were lying beneath the body, inside the nearly hermetically sealed baggage…

The man in the bag turned out to be Gareth Williams. He was a distinguished mathematician and codebreaker. He began his career at the British cybersecurity agency (GCHQ) and, at the time of his death, was working for the elite foreign intelligence agency MI6. His death remains one of the most perplexing, complex, and mysterious mysteries in recent British forensic history.

Gareth, from a small Welsh village, was an absolute genius. By the age of 17, he had graduated with top marks in mathematics, and his classmates and teachers described him as having the fastest-working brain they had ever encountered. He was an introvert, led an extremely structured life, avoided alcohol, and had passions for cycling, art, and the mountains. Some of his friends suggested that, due to his difficulty forming social relationships, he might have been on the autism spectrum.

At MI6, he worked with the American National Security Agency (NSA), helping to track international money laundering routes used by organized crime groups, including the Russian mafia. However, the London spy scene—full of glitz and after-work drinking—didn't suit him. Shortly before his death, he applied to return to the safety of his quiet office in Cheltenham. However, he never got around to it.

The detectives who entered Gareth's apartment had to answer many difficult questions. Despite the apartment being locked from the outside and the decomposing body inside in a padlocked bag, Gareth's fingerprints and foreign DNA were not found on the luggage or bathtub. The heating in the apartment was turned up to maximum, which seemed very unusual in summer. This significantly accelerated the body's decomposition, preventing toxicologists from detecting any rapidly disappearing toxins.

The case was almost immediately complicated by press leaks, which the coroner in charge of the inquest, Dr. Fiona Wilcox, later called a cynical attempt to manipulate the media and damage the victim's reputation. Women's designer clothing worth £20,000, wigs, and cosmetics were found in Williams's apartment. It was revealed that he rarely, but nonetheless, visited bondage websites. Based on this, the British Metropolitan Police (Scotland Yard) drew a shocking conclusion: the agent likely died as a result of a tragic accident during an erotic practice involving bondage and trapping himself in a bag.

This theory was denied by his family, who emphasized that Gareth was an excellent risk assessor and would never have done something so dangerous. Furthermore, Peter Faulding, an expert in confined spaces and escapology, made around 400 attempts to lock himself in an identical bag with the same padlock. He would never succeed in doing so without leaving any trace. He noted that even the famous Harry Houdini would have struggled. Despite this, after years of investigation, the police persisted with the tragic accident theory, much to the disappointment and pain of the family, who to this day believe Gareth was murdered.

Coroner Fiona Wilcox took a completely different view. Her inquest concluded that Williams' death was unnatural and "with probability bordering on certainty, caused by the criminal act of a third party." She sharply criticized British intelligence for obstructing the investigation. It is astonishing that such a key MI6 analyst failed to report to work for seven days, missed important meetings, and the agency failed to report it at all. Furthermore, police found nine flash drives in Williams' locker at MI6 headquarters, the existence of which the intelligence service had not informed investigators.

True crime experts and journalists point to several hypotheses:

• Russian Thread (Operation "Sweetness"): Boris Karpichkov, a former KGB major who defected to the UK, revealed that Williams had discovered a Russian "mole" in British intelligence. According to this version, the Russians attempted to blackmail Williams with fabricated materials damaging the agent's reputation. When this failed, he was eliminated. Karpichkov claimed that Gareth was given a psychoactive substance in wine, and after he lost consciousness, a rapidly decomposing poison was injected into his ear. Seizing the body in a bag and turning on the heating was intended to destroy evidence, and the women's clothes were planted to mislead the investigation.
• Bill Clinton's diary: The Sun on Sunday, citing anonymous sources in the interview, suggested that Williams had come into possession of the former US president's private notes and diary, which was a diplomatic nightmare due to his close cooperation with the Americans at that time.
• Murder committed by other secret services: the victim's family openly stated that the secret services were behind the death, and the lack of fingerprints and DNA, the removed locks, and the perfectly cleaned apartment indicate a professional execution carried out by experts.

Although the police and the coroner's case were polar opposites, one thing is certain: the fate of the brilliant young mathematician from Wales proves that life sometimes writes scenarios darker and more convoluted than the best spy novels. The British intelligence motto—Semper Occultus (Always hidden)—is applied here in its most grim and literal sense.