Published in 1894, 'The Parasite' by Arthur Conan Doyle is a horror tale that delves into the intersection of science and the supernatural. The story follows Professor Austin Gilroy, a physiologist who becomes embroiled in the mysterious world of mesmerism through his interactions with the clairvoyant Miss Helen Penclosa. As Gilroy grapples with his skepticism and the inexplicable powers exhibited by Penclosa, he faces a psychological struggle that challenges his rational beliefs and explores themes of obsession and the dangers of unacknowledged abilities.
