The Caves of Steel
One of Asimov's earliest and best books. Humanity has gone underground, living in cramped quarters in huge cities under the earth. But humans who
have gone to the stars and come back, called "Spacers" have developed a very different lifestyle, living in the open air with robot helpers. Humans
still on Earth hate robots and hate spacers.
But when a prominent Spacer is murdered, R. Daneel Oliver the spacer's robot (who, to complicate things, looks exactly like the murdered Spacer), is
paired up with a human detective Elijah Bailey. The story is ostensibly about solving the murder, but is really about exploring life in a regimented,
overcrowded underground megacity, while at the same time exploring what robots are and how they behave.
It seems MM is not the only one who weaves a tangelled web on this board in order to catch an unsuspecting fly.
There appear to be a whole colony of spiders.