In the company of Rupert Bedford, a grasping speculator, Samson Cavor, an elderly inventor-scientist, ascends to the Moon in a sphere coated with 'Cavorite', a substance which has the property of neutralizing the law of gravity. After strange adventures with the 'Selenites' (the inhabitants of the Moon), Bedford villainously deserts the professor and returns to Earth alone in order to make a fortune for himself out of Cavorite. By means of wireless telegraphy, however, Hogben, a young engineer in love with Cavor's niece, Susan, succeeds in getting in touch with the stranded inventor, who denounces Bedford and states that he has been amicably received by the Grand Lunar, overlord of the Selenites. Susan thereupon indignantly rejects the proposals of Bedford, who has represented it as Cavor's last wish that she should marry him, and, instead, accepts Hogben as her husband.〔