All looks set fair Major Matthew Hervey: news of a handsome legacy should allow him to purchase command of his beloved regiment, the 6th Light Dragoons. He is resolved to marry, and, rather to his surprise, the object of his affections - the widow of the late Sir Ivo Lankester - has readily consented. But he has reckoned without the opportunism of a fellow officer with ready cash to hand; and before too long, Hervey is on the look-out for a new posting. Hervey has always been well served by old and loyal friends, however, and Eyre Somervile comes to his aid with the means of promotion: there is need of a man to help reorganise the local forces at the Cape Colony, and in particular to form a new body of horse. At the Cape, Hervey is at once thrown into frontier skirmishers with the Xhosa and Bushmen, but it is Eyre Somervile's instruction to range deep across the frontier, into the territory of the Zulus, that is his greatest test. Accompanied by the charming, cultured, but dissipated Edward Fairbrother, a black captain from the disbanded Royal African Corps and bastard son of a Jamaican planter, he makes contact with the legendary King Shaka, and thereafter warns Somervile of the danger that the expanding Zulu nation poses to the Cape Colony. The climax of the novel is the battle of Umtata River (August 1828), in which Hervey has to fight as he has never fought before, and in so doing saves the life of the nephew of one of the Duke of Wellington's closest friends.