Five weeks in a hot air balloon

English scholar and explorer Samuel Ferguson has developed a new type of hydrogen balloon to make long journeys. Together with his faithful servant and friend, Dick Kennedy, he decides to cross the African continent with it. At first everything seems to be under control according to the planned route to Lake Victoria, but soon they will have to face adverse environmental conditions, but also problems with the primitive native populations... Their safe and unharmed return to England will develop into an exciting adventure.