Author James Bannon
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Going undercover with 'the firm'

Former undercover police officer James Bannon spent 2 years during the mid eighties trying to infiltrate one of football's most notorious gangs.

His story was turned into a movie, I.D, in 1995, but he remained anonymous.

That is until now, with the publication of his account of those years in Running With The Firm.

James told BBC Breakfast about his true story.