A band of immortals recruit physicist Sequoya Guess — who gains control of Extro, the super-computer that controls all mechanical activity on Earth. But the task of the merry suddenly becomes a fight for the future of Earth. Sequoya Guess must be killed. And how do you kill an immortal? Serialized in Analog Science Fiction (Nov, Dec 1974, Jan 1975) as The Indian Giver, later published in book f...