02/05/2012 08:52 BST

Gareth Williams Death: Mystery Still Surround Enigmatic MI6 Spy's Death

Gareth Williams crammed his life with secrets - in and out of work.

The 31-year-old excelled as a spy, producing "world-class" code-breaking intelligence for MI6 in London and the GCHQ eavesdropping station in Cheltenham, Gloucestershire.

However, outside of work he was enigmatic, with a network of interests.

Police, who painstakingly pieced together his unlikely interests, discovered a fiercely private bachelor fascinated by women's clothes and drag queen culture.

He enrolled on a fashion course and collected £20,000 of unworn designer women's clothing at his pristinely tidy flat, including 26 pairs of women's shoes designed by Christian Louboutin, Stella McCartney, Christian Dior and Chloe.

Small and medium-sized dresses were also hung up in pristine condition wrapped in tissue paper in his wardrobes along with women's wigs, including one Mr Williams had bought on a recent trip to Las Vegas.

Mr Williams interests were a far cry from the rigid discipline of work, where he was fast-tracked through the ranks at GCHQ before arriving at MI6.

is boss at GCHQ's Cheltenham base, Stephen Gale, said Mr Williams stunned fellow intelligence specialists with his code-breaking talents when he landed his first job at 21.

Bosses were so impressed that they paid for him to gain further qualifications in advanced mathematics at Cambridge University.

Mr Gale said: "He was considered something of a prodigy and it was quite remarkable that he had achieved those levels of qualifications at such a young age.

"Colleagues recall a young man who was very close to his father - he spoke about their climbing trips together.

"They remember him as a keen cyclist. One colleague said it was like a red bullet flying around the place."

Mr Williams had won two awards at GCHQ, one for a "Herculean effort" in his top secret work, Mr Gale added.

In the months before his death he passed an exam to become fully operational with MI6. His examiner said in a report: "I was particularly impressed with Gareth. This was definitely the most intense operational course that I have seen and the improvement needed was immense."

But sister Ceri Subbe said: "He disliked office culture, post-work drinks, flash car competitions and the rat race. He even spoke of friction in the office."

Ms Subbe said her brother was immensely close with his family, from Anglesey, Wales.

"In terms of a big brother figure, Gareth was perfect," she said.

"It's impossible to do justice to Gareth's impressive character without meeting him."

Jackie Sebire, the detective who led the inquiry into his death, said he should be showered with praise for his work in keeping Britain's shores safe.

Mr Williams was a "brilliant young man", she added.

Today, the coroner overseeing the inquest into his death, Dr Fiona Wilcox, announced that she will eliminate unlawful killing as a cause of his death due to an absence of evidence to prove it.

Dr Wilcox is expected announce an open verdict in the inquest.