British Gangs covers the first fifty years of the twentieth century, a time of upheaval and war during which the public came to fear groups of young men. Much of this fear was whipped up by an expanding newspaper industry trying to increase sales with alarming and salacious stories. The book finds that the gangs were not as big a menace as the public were led to believe, but their activities are no less thrilling or important in the present day. This is a gripping account of one aspect of working class life.

It covers the better-known gangsters of the time such as the McDonalds, Sabinis and Cortesis, Alf Solomon and Billy Kimber, but also, as a result of days spent in newspaper archives, uncovers many stories as they were reported at the time. Car and bus chases, gun battles, shoplifting, violent activity at sporting events, simple street con artists and more are all included in this trove of gang stories, most of which have been forgotten.

The book covers many lesser-known incidents and stories from Britain's gangs, including a look at female criminals such as Alice Diamond, Mary Carr, Florrie Holmes, Kathleen Cooper and Josephine O'Dare, and the successful nightclub owner Kate Meyrick. Gangs from around the country are included, in cities including Manchester, Liverpool, Glasgow, Hull, Sheffield, Newcastle, Leeds, Belfast and Dublin, as well as the more often-covered Birmingham and London. Prison time also features, as an important part of a criminal's life that is not often included in books on gangsters. This is an important contribution to the recorded history of British gangs.