<description>&lt;p&gt;With so many unanswered questions, different theories about what exactly happened to young Welshman Gareth Williams in summer 2010 remain rife. One suggestion is that he was assassinated by a rogue state. A former KGB intelligence officer, an ex-Government Minister and the wife of murdered dissident Alexander Litvinenko all suspect Russian involvement. But would the Kremlin really go to such lengths?&lt;/p&gt;&lt;p&gt;Death of a Codebreaker is presented by Dr Sian Williams with contributions in Episode 4 from from Dyfan Rees, Ashley Byrne and Wayne Wright.
Producers: Ashley Byrne, James Pepper and Wayne Wright
The Executive Producer is Ashley Byrne.
Research by Wayne Wright, Ashley Byrne and James Pepper.
Music by Robin Forrest
The Sound editor: Kev Bailey
Death of a Codebreaker is an MIM Production for BBC Sounds and BBC Radio Wales.&lt;/p&gt;</description>

Dr Sian Williams charts the story of Gareth Williams, the codebreaker found naked in a bag

<p>With so many unanswered questions, different theories about what exactly happened to young Welshman Gareth Williams in summer 2010 remain rife. One suggestion is that he was assassinated by a rogue state. A former KGB intelligence officer, an ex-Government Minister and the wife of murdered dissident Alexander Litvinenko all suspect Russian involvement. But would the Kremlin really go to such lengths?</p><p>Death of a Codebreaker is presented by Dr Sian Williams with contributions in Episode 4 from from Dyfan Rees, Ashley Byrne and Wayne Wright.
Producers: Ashley Byrne, James Pepper and Wayne Wright
The Executive Producer is Ashley Byrne.
Research by Wayne Wright, Ashley Byrne and James Pepper.
Music by Robin Forrest
The Sound editor: Kev Bailey
Death of a Codebreaker is an MIM Production for BBC Sounds and BBC Radio Wales.</p>

Death of a Codebreaker

4: Russia

4: Russia

Description