What turns a fan into a fighter? When faced with a choice, do you turn and run, or stand and fight?
We meet the men who found themselves drawn into a world of running battles and riots during the 1970s and 80s. For some, joining a firm and fighting gave them a new identity. For others, it was the first time they truly felt they belonged.
From a young age, Bill Gardner, also known as Mr West Ham, found a home and a family he never had on the terraces of Upton Park, one he would fight for. For adopted Brummie Cockney Al, the early firms in Birmingham took him under their wing, but it was not long before he was up to his neck in it. In Manchester, a childhood plagued by bullying and racism led Fireman Sam to become part of United's hooligan mob, and for Chelsea fan Mark Alleway, being a football hooligan became an addiction.
But not everyone was signing up. Most fans just wanted to go to the game in peace, but trouble was never far away. Football writer Amy Lawrence and DJ Trevor Nelson recall how getting out unscathed on matchdays was not always easy.
The police and politicians soon realised they had a serious problem on their hands. But despite their best efforts, the mobs ruled the terraces. And for a while, it was chaos.
Presenter: Tony Bellew Series Producer: Emma Forde Producer: Patrick Kiteley Technical Producer: Nicky Edwards Editor and Executive Producer: Carl Johnston Development Producer: Holly Clemens With research assistance from Abe Atchia Production Co-ordinator: Ellie Dover Assistant Commissioner: Lorraine Okuefuna & Sarah Green Commissioning Editor: Louise Kattenhorn