Far into the future, Hartstein's graduation present from his grandparents was a wonderful trip.into the past. He had a long future in the doughnut industry to look forward to but this trip was the icing on the cake. It had been a long time since that first experiment in time travel was successfully pulled off, although not without its flaws. Now, in the future, time travel was a lucrative tourist industry. But the time travel industry was keeping one little fact to itself: two percent never came back. This cover-up was the work of the Agency. The Agency knew what others did not: that the past wasn't really the past but a complicated dynamic of individual perceptions of what the past might have been. The past isn't real and reality becomes a state of mind. While selling their particular brand of escapist entertainment and vacation packages, the Agency didn't bother to tell its clients or the populace in general that a war was going on- a time war. The Agency was spending its time in a neck and neck battle with the Temporary Underground. The battlefield was none other than the space-time continuum, the weapons time shifts and theoretical mathematics. Hartstein had no idea what his trip would be or where it would take him.
Used availability for George Alec Effinger's The Bird of Time
April 1986 : USA Hardback
May 1988 : UK Paperback