On the bucolic farming planet of Terr'ferme, Rabbs din Chorest, the fifteen-year-old youngest child of the Chorest-Grant, has just been made Hand, being sent to the Blackmarker Hills to tend a herd of clorses (cloned horses) and beefers. Not far away is the ruin of Spiretown, a long-abandoned place of the Old-uns, a race that had once inhabited this world.

Then the Knack's invade, destroying settlements, devastating ranches, and harvesting human and large animal flesh for reprocessing as food. Rabbs is cut off from civilization, with no way of communicating with the outside world. When a party of refugees appears, they become the Hand's responsibility as well. Trapped by a bug troop in a cave near the ruined alien city, the humans have nowhere to go and no one to ask for help.

Will anyone survive the Knack' attack?