In August 476, Zeno besieged Constantinople. The Senate opened the gates of the city to the Isaurian, allowing the deposed emperor to resume the throne. Basiliscus fled with his family to the baptistery of Hagia Sophia. Betrayed by the Patriarch Acacius, he surrendered himself and his family after extracting a solemn promise from Zeno not to shed their blood. Basiliscus and his family were sent to a fortress in Cappadocia, where Zeno had them enclosed in a dry cistern, to die from exposure.