On July 26, 1945, the United States, China, and Great Britain issued the Potsdam Declaration to Japan, in hopes of putting World War II to an end without further bloodshed. The declaration closed with an ultimatum: "We call upon the government of Japan to proclaim now the unconditional surrender of all Japanese armed forces, and to provide proper and adequate assurances of their good faith in such action. The alternative for Japan is prompt and utter destruction." On September 2nd — after two atomic bombs hit its cities, the Soviet Union invaded its territory, and American B-29s bombed its shores — Japan officially surrendered. The signing ceremony took place on the deck of the USS Missouri and, for the first time in years, the world was at relative peace.
But if it were up to a small cadre of Japanese, the surrendered would have never happened. This group, led by a high-ranking member of the Japanese military, attempted to prevent the surrender — not by overthrowing the empire, but by stealing a record.
From 1868 until 1947, Japan's sovereignty was invested in a monarch — the Emperor of Japan — who was said to be an a divine being in human form. (Japan still has an emperor but the position is no longer considered to be God-incarnate, just, perhaps, a descendant of some higher power. Either way, the emperor is now only debatably the head of state and, even if so, it's a figurehead position.) What the emperor said, the nation did. On or around August 9, 1945, Emperor Showa (also known as Hirohito) — the monarch at the time — decided to accept the Potsdam Declaration. The democratically elected government, unsurprisingly, agreed. To announce the surrender, Hirohito ordered a drafting of a statement, to be read by him, explaining the reasons for accepting the Declaration while (in his eyes) protecting the sovereignty of his rule.
Many high-ranking military members disagreed with the decision, but few if any were willing to overthrow the empire. However, a small group of about 1,000 soldiers, led by a major named Kenji Hatanaka, had an idea: the Empire wouldn't capitulate if the Emperor's words were never broadcast. So Hatanaka and company set forth, hoping to prevent that exact result.
By quirk of culture, this could be accomplished without kidnapping or otherwise disturbing Hirohito himself. It was unheard of for the Emperor to address commoners — few members of the Japanese populace had ever heard Hirohito's voice — and the surrender statement was only a limited exception. While commoners were going to hear Hirohito's voice, perhaps for the first time, they were not going to hear it live. Instead, it was recorded to a phonograph record and, on August 14th, broadcast throughout the nation via radio in what is now known as the Jewel Voice Broadcast. Hatanaka knew of this plan and, therefore, set out to steal and destroy the record before it could air. On the 14th, his ad hoc army raided the Imperial Palace in search of the four minute, 41 second speech which would end the war.
Unfortunately for Hatanaka (and thankfully for a war-ravaged world), the mysteries surrounding the lives of the Japanese imperial class extended deeply — including into the architecture of their homes. Hatanaka and company, despite their best efforts, were unable to navigate the labyrinth design of the palace and therefore, unable to find the recording. According to Wikipedia, the record was "successfully smuggled out of the palace in a laundry basket of women's underwear." The recording then made its way to a radio station and, ultimately, broadcast throughout the nation.
Hatanaka took his own life after his coup failed.
Bonus Fact: Even after Hirohito's message was broadcast, many Japanese citizens were confused as to what happened — not because the message of surrender was unexpected, but because it was incomprehensible to them. Hirohito used a formal dialect called Classical Japanese, which had fallen into disused a generation earlier among those who weren't lucky enough to be born with imperial blood (or were cultural elites for other reasons). Many Japanese couldn't understand what his message meant (and he didn't actually mention "surrender" but instead an acceptance of the Potsdam Declaration). The radio host, after Hirohito's address, explained what had just happened.