Before the railway system linked South Africa’s major cities in the mid-1890s, the country was largely dependent on a horse-drawn economy. Diamonds from Griqualand West and gold from the Witwatersrand were transported by coach and horses to distant ports for export. For some Irish soldiers based at Fort Napier in Pietermaritzburg, this temptation proved impossible to resist: they deserted in droves and, as members of what later became known as the criminal "Irish Brigade," they embarked on a spree of bank, safe, and highway robberies across southern Africa.

With tales of heists, safe-cracking, illegal gold dealings, prison breaks, and hidden roadside treasure, Masked Raiders follows the exploits of legendary Irish brigands such as the McKeone brothers and "One-Armed Jack" McLoughlin, who ravaged the subcontinent, from the mining towns of Barberton, Kimberley, and Johannesburg to the borders of Basotholand, Bechuanaland, Mozambique, and Rhodesia in the years leading up to the Jameson Raid in South Africa.