The imam who is in hiding is Muhammad al-Mahdi.
Muhammad al-Mahdi, also known as the "mahdi" (meaning "divinely guided one"), is a central figure in Twelver Shia Islam. According to Twelver Shia beliefs, he is the twelfth and final imam. In 874 A.D., as a six-year-old, he went into hiding (referred to as ghaybah) to protect himself from persecution by the Abbasid Caliphate.
The concept of the "hidden imam" is a cornerstone of Twelver Shia theology. It is believed that Muhammad al-Mahdi will reappear at a future time to bring justice and peace to the world. His absence is a trial for the faithful, and they are expected to remain steadfast in their beliefs and await his return.
While in hiding, it is believed he is still present in the world, but concealed by God. He is sometimes referred to as the "Living Imam" or "Imam of Our Time." His role is to guide the faithful and ensure the continuation of divine guidance until his reappearance.
Therefore, Muhammad al-Mahdi is the specific imam who remains in occultation, awaiting God's command to reappear.
