the company builds planets. kin arad is a high-ranking official of the company. after twenty-one decades of living, and with the help of memory surgery, she is at the top of her profession. discovering two of her employees have placed a fossilized plesiosaur in the wrong stratum, not to mention the fact it is holding a placard which reads, end nuclear testing now, doesnt dismay the woman who built a mountain range in the shape of her initials during her own high-spirited youth. but then came discovery of something which did intrigue kin arad. a flat earth was something new...first published in 1981, strata is an early exploration of the idea that was to become the bestselling discworld series.