In 1976, Phyllis Gotlieb published O

Master Caliban/ In that novel, genetic

scientist Edvard Dahlgren populated a

barely habitable planet with mutants and

man-serving machines. The machines, or

ergs, rebelled against their slavery and

slaughtered their masters, touching off a

war for control of the planet that destroyed

the budding civilization.

In Heart of Red Iron, Dahlgren s son

Sven--who had been genetically altered

by the ergs to punish his father--returns to

the planet Barrazan V. He is part of a

colonizing mission funded by Sir Freder-

ick Havergal, but Havergal has a different

agenda which Sven will uncover. With

Sven are his wife Ardagh, a physician; his

mechanical twin Mod Dahlgren, a survi-

vor of the erg war; and two alien cultures,

the Meshar and the Yefni, both suited for

life in the climatic extremes of Barrazan V.