On September 1st, 1939, Nazi Germany invaded Poland from the West. On September 17th, the Soviet Union did the same from the East finally fulfilling its obligations under the Molotov-Ribbentrop Pact.
On September 28th, the Warsaw garrison surrendered to the victorious Wehrmacht. On October 5th, Adolf Hitler arrived in Warsaw to inspect and honor his troops marching in the streets of the conquered Polish capital in an impromptu parade.
Neither Hitler nor his security services (nor anyone in German armed forces) even suspected (let alone knew) that on that day only a genuine miracle saved Der Führer from being assassinated.
Individuals that developed and (almost) executed this straightforward and in a way massive plot were foreigners again – but this time the agents of a foreign power. More specifically, they were the officers (and generals) of a just a few days ago defeated Poland.
These brave individuals (the real Polish knights) refused to surrender and vowed to continue fighting the Nazi Germany – now as guerillas. Partisans. Members of the Polish Resistance which ultimately became Armia Krajowa (AK) – the heroic “Hoem Army” of the Polish government in exile (a military arm of the Polish Underground State).
On September 27th, just one day before Warsaw capitulated before Wehrmacht, Polish general Juliusz Rómmel (no relation to the Desert Fox) who was in charge of the defense of the Polish capital, ordered his second-in-command – General Michał Karaszewicz-Tokarzewski to create the Słuzba Zwyciestwu Polski (“Service for Polish Victory”) – the first Polish resistance organization in World War II.
General Tokarzewski was a brave officer, a highly creative commander and (like Adolf Hitler) a firm proponent of the most radical solution to the problem at hand. Hence he ordered his subordinates… to assassinate Adolf Hitler during the Warsaw victory parade (of which absolutely self-confident Nazis made no secret whatsoever).
The solution that SZP members came up with was, indeed, radical. Devastatingly radical, I would say. A 500-kg bomb filled with 220kg of high explosives (TNT) was skillfully concealed in a ditch to be detonated when Der Führer showed up.
Had it been detonated, Adolf Hitler would surely have left our world in an unknown destination – and definitely in some very small pieces. However, the Providence saved him again – at the last moment the parade was diverted, Hitler never showed up near the bomb and the Polish officers had no other choice but to abort the detonation. The bomb was dug out and disarmed only after the war.