Second Stage Lensman — E.E. "Doc" Smith

Interplanetary spy

Kim Kinnison was Number One Man of his time.

To him fell the incredible assignment of infiltrating the inner circle of Boskone. Kinnison's deadly job was to become a Boskonian in every gesture, thought, and deed. He had to work himself up through the ranks of an alien enemy organization, into the highest echelons of power--until it was he who would be issuing the orders that would destroy his own civilization!