Following several days of persistent rain in northern India, Captain James Ogilvie of the 114th Queens's Own Royal Strathspeys is one of many British soldiers ordered east from Peshawar to help with the evacuation of flooded Patna. Meanwhile a tidal wave from the Ganges maroons Lieutenant-General Fettleworth in a native hut, and news filters through that the floodbound Rawalpindi-Calcutta train has come under attack from the Pathans. On board the train is 100,000 worth of gold bullion belonging to the Raj, highly desirable to the Pathans, which Ogilvie is immediately sent to rescue. A dangerous game of bluff and double bluff ensues, with Ogilvie at its centre as the flood recedes and time quickly runs out.