New York, Walker, 1972. First US edition. Unbeknownst to Earth, a superintelligent alien is plotting the destruction of the human race. No children have been born in months, and the population is shrinking. Enter Dr. Palfrey and Z5. Can they save humankind in time? Small stain to front endpaper and to boards. Spine slightly cocked. Slight touch of wear to dust jacket spine ends and blue stripes to DJ from the Brodart cover. $7.50.