There are androids on Earth that help people with their needs, they talk like humans, they look like humans and they act like humans. They are manufactured on the planet Mars and they have Artificial Intelligence. Androids however are not human and therefore do not have the same rights as humans. Every now and then androids escape from Mars and head to Earth illegally and it is the job of bounty hunters to "retire" them. How do these bounty hunters tell androids and humans apart? Androids don't have empathy.
Do Androids Dream of Electric Sheep is a book by Philip K. Dick who's book was made into a movie called Blade Runner. His story follows a bounty hunter called Rick Deckard and his journey in retiring the newest android models the nexus-6. Dick does not just write a simple science fiction book but delves much deeper philosophically and psychologically. Deckard goes through a lot of information while hunting down the 6 renegade androids. He is paranoid of everyone, because androids and humans look a like he has to administer empathy tests on practically everyone he meets even himself. He starts feeling empathy towards non-living objects and has to deal with all this and make a living.
To my surprise I actually really liked the book. I loved the psychological and philosophical aspects of the book. It wasn't all about action sequences and they actually took a back seat. The ending perhaps was a little anti-climatic because I had all these different endings in my head, but expectation almost always leads to disappointment.
If you have seen the movie Blade Runner and didn't like it, I suggest you read the book because I was in the same boat as you.