In Southampton, near Stonehenge on the south coast of England, some of the world's greatest minds in physics meet for their annual symposium. Philip Blackmore, a professor from Cambridge University is well prepared for the meeting, but not for the proposition that he receives from a group of American colleagues. They want him to join a team that will build a machine that can see into the past. Not a time machine, beloved of science fiction, but outside the laws of physics, but a machine that can recover images of past events.Philip's initial reservations are overcome by Carol Dunning, a brilliant young graduate student from Cal. Tech. who returns with Philip briefly to Cambridge. The College agrees to grant him a sabbatical and he leaves with Carol and a graduate student to join the team at MIT in Cambridge, Mass. Project funding is provided by a mysterious philanthropic scientific foundation that is very generous, but swears them to secrecy.Even before the project starts, however, a string of mysterious accidents begin to plague the physicists and it quickly becomes apparent that someone is determined to stop the project at all costs. But who? And why?