Ali and his two sons, Hassan and Hussein, are the first three imams. Various Shia schools differ in the number of recognized saints: five among the Lebanese Druze, seven for the Ismailis, led by the Agha Khan. Iranians believe in twelve imams. The twelfth, Imam al-Zaman, or the Saint of All Time, mysteriously disappeared in the tenth century. He is the Shia messiah, or madhi, living in hiding, who will reemerge on judgment day to restore justice on earth. Throughout Iran, silent prayers are offered for his return.
