Professor Benjamin Tibbets (Will Hay) goes up river in Africa to open schools for natives. At the same time, Commissioner Sanders leaves the base on leave and Mr Hamilton takes over as deputy.
School starts and Professor Tibbets has a hard time with his new pupils, but then Mr Hamilton goes down with Malaria so Tibbets decides to take on his duties as well.
Then Tibbets starts to collect the local taxes abbeted by the crew (Graham Moffat, Moore Marriott). He manages to stir up the situation into a full scale native revolt and ends up only just escaping with his life!