When two award-winning science-fiction masters like Anne McCaffrey and Elizabeth Ann Scarborough collaborate, the results are astonishing. Their master creation is Petaybee, a sentient planet able to guide its own evolution and, with some help from its loyal inhabitants, defend itself against predation by offworlders. Now, at last, McCaffrey and Scarborough return to Petaybee for the thrilling conclusion of the Twins of Petaybee trilogy, the sixth novel of the amazing self-aware world. DELUGE InterGal Corporation has long desired to exploit the resource-rich Petaybee. But the planet and its guardians, led by Yana Maddock and Sean Shongili, along with their twin children, Ronan and Murel, have successfully thwarted every attempt by the Corporation to impose its iron-fisted dominion. Until now. In a bold two-pronged assault, the predacious Corporation has arrested Petaybee’s leading off-world champion, Marmion de Revers Algemeine, on trumped-up charges, while InterGal’s military arm has dispatched an invading force to subdue the planet once and for all. Marmion has allies within the Corporation who can halt the invasion. but if they cannot be found quickly, it will be too late for Marmion . . . and Petaybee. While their parents work to foil the invasion of their world, Ronan and Murel are captured and sent to a desolate prison world where an old enemy, Dr. Mabo, waits to continue her cruel experiments on the shape-changing siblings. The twins’ only hope of escape lies in the uncharted seas of the prison planet. But in the murky depths, something else is waiting. . . . Praise for Anne McCaffrey and Elizabeth Ann Scarborough “Excellent, fast-paced action [makes the] story hard to put down: fans of either McCaffrey, Scarborough or their previous books on the topic will all be enthusiastic readers.” –The Bookwatch, on Maelstrom “The story is exciting and generously laced with humor, but besides those qualities, the characters . . . and their interactions are so well realized as to utterly charm readers.” –Booklist, on Changelings “Anne McCaffrey and Elizabeth Ann Scarborough collaborate seamlessly to tell a first-rate sf adventure with strong male and female protagonists and a life-affirming theme.” –Library Journal, on Power Lines “Well-handled far-future speculation on ecological engineering and planetary consciousness . . . [an] agreeably colorful, well-realized adventure.” –Kirkus Reviews, on Powers That Be Anne McCaffrey, the Hugo Award—winning author of the bestselling Dragonriders of Pern novels, is one of science fiction’s most popular authors. She lives in a house of her own design, Dragonhold-Underhill, in County Wicklow, Ireland. www.annemccaffrey.net Elizabeth Ann Scarborough, winner of the Nebula Award for her novel The Healer’s War, is the author of numerous fantasy novels. She has co-authored ten other novels with Anne McCaffrey. She lives on the Olympic Peninsula in Washington State. www.eascarborough.com Chapter 1 The sentient world Petaybee, its northern continent blanketed in snow, appeared deceptively serene. Cold enough to freeze a sneeze in midair, but peaceful beneath its dark sky, it seemed an easy target for the troops whose arrival disturbed that peace. Although they knew that the people in the village of Kilcoole were hostile and armed, the Company Corps soldiers did not worry unduly about resistance. Their landing was unannounced and they believed unexpected, so their superiors were confident that the soldiers could simply storm into house after house, waking the villagers and hauling them from their beds while they were still befuddled by sleep. Instead, the soldiers were the ones who were befuddled as they slammed open unlocked door after unlocked door to find vacant unheated rooms with ice frosting the inside walls. Wild animals darted down the street or across it but no domestic beasts or human beings remained in the village. The sergeant in charge of the ground mission regarded the village suspiciously. “Fan out and search but be damned careful,” he ordered. “These people are hunters. They won’t be far and they’ll be watching us.” He returned to his flitter, kept running and warm by the driver, and called the captain on the com. They’d hoped the blade of the Petaybean winter would still be a few weeks away but it seemed they were out of luck. Much of their equipment would be useless now with the extreme cold. “They’re gone, sir.” “I doubt that, Sergeant,” the officer replied. “They must have been warned. Now we’ll have to pursue them outside the village on their own turf. I’ll consult High Command. Meanwhile, search the houses and see what intelligence you can gather. The gover- nor’s mansion is a log cabin at the end of the street nearest the river. Seize records of any kind, books, computers, storage chips— anything. If they make grocery lists in this godforsaken hole, I want those too. Governor Shongili has a laboratory west of the village, according to our