Reactionary 23rd-century terrorists will change history unless the elite Anti-Revision Command, the ARC Riders, aided by war veteran Maj. Rebecca Carnes, can find them. In a manhunt that ranges from the 26th century to 50,000 B.C., the ARC Riders must stop the killing before they lose their one chance to untie the fatal knots of time.
Used availability for David Drake's ARC Riders
June 1995 : USA Mass Market Paperback
September 2009 : USA, Canada Kindle edition