During a savage Mahdi attack on Barash under Victorian British rule, Richard Baker, thrice demoted sergeant, rescues an English governess, her charge and a callow subaltern. Baker hopes to escape by river to Khartoum but the wreckage of their boat and a narrow escape from slave traders force the party overland. Murchison's attempts to take command and Miss Woodville's disapproval dwindle in face of Baker's courage and resourcefulness. Finally captured by natives, themselves in danger from the Mahdi forces, they engineer their escape through tribal dissension. Murchison's knowledge of the nearby British garrison which is under attack, enables them to blow up the arsenal and save the day. Murchison is commended for bravery and Baker arrested for desertion but it is Baker who wins the lady.