The Caves of Steel

I found a book that had three Asimov 'Robot' novels in one at the library. I have actually read them all before, but read them all again anyway.

The first was The Caves of Steel. Way in the future, men on Earth live in huge megalopolises that are completely enclosed. They never go outside, hence the title. About 50 worlds have be colonized by 'spacers', who have no disease and live 350 years. Neither earth men or spacers trust each other. On Earth, robots are used, but not really trusted. On the spacer worlds, robots are a virtually unlimited source of free labor.

There is a spacer colony on Earth, sort of like an embassy, only larger. One day, a spacer is murdered. The spacers refuse to believe one of their own did it, so it must be a human. Elija Bailey, plainclothes detective, is brought in to investigate. He is assigned a partner, who is the only (known) completely human-form robot. He is almost indistinguishable from a human being.

There is much talk between the uneasy partners about how and why both sides act how they do, and what is best for humans. Ultimately, they actually become friends, and solve the mystery. It's a pretty fun read, and a good mystery to book.