The Assassins, established in Iran and Syria in the 11th and 12th centuries as an offshoot of the Ismaili Shi'ite sect of Islam, aimed to overthrow the existing Sunni order, and word of the group reached Europe by way of the Crusaders. Lewis studies the history and influence of the group in this insightful account, putting recent terrorist events into a historical perspective.  (IRN41, $15.95)