"This book contains information for gamemasters who wish to design adventures featuring these foes of The Doctor. Exercise care when gamemastering Cybermen because they are EXTREMELY powerful fighters. Do not place player characters in direct combat situations with large numbers of Cybermen. Otherwise, the gamemaster will soon have several dead characters on his hands."
This sourcebook contains information about another of The Doctor's famous enemies, the Cybermen. The product is split into two books. "The Cyber Files - CIA Special Report" is a sparse 16-page book meant for the players, purportedly written by the "Celestial Intervention Agency" and meant as an official, albeit sparse, history of the Cybermen. "The Cybermen" is a more traditional 48-page sourcebook for the GM's eyes only, with more elaborate information about the Cybermen.