By the year 2040, humans have reached an average life expectancy of 110 years. Many of these centenarians choose to spend their last years in retirement habitats on exotic islands. They are served by intelligent robots that are governed by globally enforced laws.

Against the backdrop of climate change on a retirement habitat, this story is woven around the potential capability of the Fifth Law of Robotics being developed by a young robotics researcher. The Fifth Law promises to champion a "spirit of brotherhood" amongst robots. Enabled by this law, a team of robots and humans led by the habitat's head successfully executes a treasure salvage to fend off the takeover of their island by a billionaire developer.

The story also tackles the themes of aging, climate change, and South China Sea politics in a web of subplots that pit humans against humans, humans against robots and robots against robots.