The second of three novels that bridge from the robot stories into the Foundation stories. This one has the early days of Trantor as a fledgling galactic empire.
This story concerns a planet, Florina, that is being held in slavery to farm a fibre known as kyrt. Kyrt cannot be grown on any other planet, even when the soil and lighting is matched, and so Sark, the slaver planet, is the sole supplier of this super fibre to the rest of the galaxy.
One day, a scientist, working for Trantor, discovers that Florina is going to be destroyed, but the scientist vanishes before anyone finds out. Thus begins the search by Trantor, Sark and others to find this scientist.
Meanwhile the scientist has had his brain wiped with a psychic probe and is being forced to work as a slave on Florina, but his memories are slowly returning.
A really fun search, chase, escape, run away and back again, ensues.
Will all be revealed before the end?
Another brilliant piece of writing by Isaac.
Next up is Pebble in the Sky.
