Muammad al-Mahdī al-ujjah

Muḥammad al-Mahdī al-Ḥujjah, also called Muḥammad al-Muntazar, the Hidden Imam, or the Twelfth Imam   (disappeared 878), 12th and last imam, venerated by the Ithnā ʿAshariyyah, or Twelver sect, the main body of Shīʿite Muslims. It is believed that Muḥammad al-Mahdī al-Ḥujjah has been concealed by God (a doctrine known as ghaybah, or occultation) and that he will reappear in time as the mahdi, or messianic deliverer.