A science-fiction novel and detective story by Isaac Asimov, devoted to the adventures of two future detectives—Elijah (in another version Ilayzha) Bailey, a human from Earth, and the cosmonaut robot Daniel Olivo.
The novel describes an investigation into the murder of one of the representatives of Earth’s colonies—the Outer Worlds. The case of the cosmonaut’s murder, which could bring disaster upon the overcrowded Earth, is led by class C-5 detective Elijah Bailey. The cosmonauts assign him as a partner R. Daniel Olivo, who simultaneously begins learning about Earth’s culture—so different from the culture of the Outer Worlds.