We had arrived at Jamkaran, a holy shrine outside the Iranian city of Qom and site of a water well where the 12th and last imam of Shia Islam, the Mahdi, is said to have disappeared a little over a thousand years ago. Many Iranians believe that the so-called hidden imam, or "imam zaman" (lord of all the ages), will at any moment choose this place to make his return to solve the world's problems. In recent years, the millenarian cult of the well of Jamkaran has become so popular that a hotel has been built nearby and the old...