An in-depth look at the most famous gangsters in British history; Secrets of the Krays features revelatory interviews with those who knew the Krays best, including former gang members, relatives and family friends, as well as celebrity photographer and friend David Bailey, the Krays' lawyers, and police officers involved in bringing them to justice.  Many have never spoken before – including Micky Fawcett who was a key member of "The Firm" from its early days.  The documentary will also unveil never-before-seen artefacts, including Reggie's personal scrapbook documenting the brothers' crimes, Reggie's personal photographs, audio recordings from prison, a poem from Ronnie to Reggie, and two unpublished manuscripts from former gang members – as well MI5 files on the Krays.