A new documentary charting the rise and fall of The Krays starts tonight on ITV.
The three-part series promises to be the most definitive account of Britain's most notorious gangsters.
The first episode will show Ronald and Reginald's early life in Bethnal Green and early steps into London's underworld.
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The twin brothers rose to power through protection rackets and became national figures following their move to the West End in 1964.
Tuesday's programme will include discussions with figures including world-famous photographer David Bailey; Kray family friend Maureen Flanagan - and former gangster Chris Lambrianou, who was sentenced to 15 years alongside the Krays.
The East End clubs run by the Krays became the fashionable place to be in the Capital - which prompted Ronnie to declare him and his brother as "untouchable".
He said: “In the 60s, the Beatles and the Stones ruled the music world; Carnaby Street ruled the fashion world and me and Reg ruled London. We were fu**ing untouchable.”
The twin brothers attempted to expand their criminal operation to Liverpool, but the Krays struggled to gain a foothold in Merseyside.
Former nightclub owner Roy Adams documented their attempts to takeover the city in his book on Merseyside nightlife titled Hard Nights: My Life In Liverpool Clubland.
Roy was known as the King of Clubs during the 60s and said the Krays made occasional visits to the city.
He recalled how a member of the force apprehended Ronnie after witnessing a vicious fight between locals in the Seel Street/Berry Street area.
Roy claims a detective took Ronnie into a telephone box and threatened him at gunpoint.
He told the ECHO in 2008: "He'd been issued with the firearm for a police security job that day although they hadn't given him any bullets!"
Roy said a member of the Kray gang allegedly told a Liverpool doorman the notorious criminals were in shock after the incident and claimed "there'll never be a protection racket in Liverpool."
Roy said he was anxious over the next few weeks as speculation grew a crew of London gangsters were making a similar move in Merseyside.
However, he was relieved to find out that the criminals realised the city wasn't for them.
He said: "I was later told that they'd been here, weighed up the Liverpool attitude and decided they didn't fancy it."
Secrets of The Krays airs tonight on ITV and ITV Hub at 9pm
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