Enter the perilous depths of space in Doctor by Murray Leinster, a gripping science fiction novel of medical suspense, interplanetary danger, and humanity's fight for survival. Aboard the starliner Star Queen, Doctor Nordenfeld faces a terrifying threat when a young survivor from a ruined world may carry chlorophage, a deadly virus capable of wiping out everyone on board. Blending classic space adventure with biological mystery, alien worlds, and high-stakes ethical choices, this fast-paced novel delivers tension, sacrifice, and scientific ingenuity in equal measure. Ideal for readers of vintage science fiction, pandemic thrillers, and Golden Age speculative fiction.