Armadale is of interest for several reasons. First, the novel centers on issues of fate. Are our destinies determined, or can they be altered? The two heroes of the novel, Ozias Midwinter and Allan Armadale, are born under a curse. Midwinter's father murdered Allan Armadale's father. On his death bed, Midwinter's father warns that if these two sons ever meet, tragedy will occur. Midwinter learns the story and is uncertain whether to leave Allan or to work at changing their fate. Collins does not offer a solution, but provides plenty of opportunity for discussion.

Second, there is a doctor in the novel whose behavior is unethical to say the least. When the reader is first introduced to him, he is running a clandestine abortion clinic. When that operation is shut down by the police, he opens a private sanitarium. He privately confesses to being utterly uninterested in his patients' health. He only wants their money.

When the local ladies come to tour the facilities he espouses a system of liberal care, including dances, fine meals, and edifying concerts on Sunday evenings. However, the building is laid out with an intricate system of pipes that allow the doctor to keep his patients continually sedated. At the novel's end, the doctor helps plan a murder using those pipes.