Dr Jekyll and Mr Hyde explores many themes including the duality of human nature, good vs evil, and the struggle between rationality and the supernatural. The novel portrays Dr Jekyll as a respected man of science and Mr Hyde as his violent, evil alter ego. It suggests that within all people lies an internal struggle between good and evil. The characters keep many secrets and do not fully express themselves, showing the difficulties of communication. Ultimately, the story is an allegory for the battle between the light and dark sides of human personality.