The failed military coup that tried to stop Japan's surrender broadcast was the Kyūjō incident.
The attempted coup began on the night of August 14, 1945, shortly before Emperor Hirohito's recorded announcement was scheduled to air. Officers from Japan's Imperial Guard and sympathetic army units sought to prevent the emperor's surrender message from reaching the public.
The plotters occupied parts of the Imperial Palace and searched for the recording. Palace officials had hidden it, however, and the conspirators failed to locate it. Senior commanders did not provide the support the rebels needed, and the coup collapsed by the morning of August 15.
Hirohito's broadcast then went ahead at noon. The incident illustrates how surrender was contested within Japan's military leadership even after the emperor and government had decided to accept the Allied terms. The name Kyūjō refers to the Imperial Palace.