On the 17th of August 1987, Hitler's former deputy Rudolf Hess commits suicide in prison. It seems the 93-year-old hanged himself in the notorious Spandau prison for Nazi war criminals near Berlin. It marks the end of a life of mystery and intrigue. We investigate some of the riddles still surrounding Hess. What motivated him to single-handedly fly to Scotland on a secret mission in May 1941? Did he want to make peace with the UK? Whatever it was, it ended with his life-long imprisonment. And we explore Hess's last mystery: did he really kill himself or was he murdered – the last remaining prisoner at Spandau.

US scientists worked feverishly on developing the first atom bomb. They feared Hitler's Germany was about to build it before them. Later it was reported that the Germans had abandoned their plans. According to new documents, allied military reports and existing construction plans, Hitler had already tested a new kind of nuclear weapon in March 1945. How far did the Germans really get?

For decades after the end of World War II, rumours persisted that the mountains of southwest Poland held a precious secret—a mysterious train laden with tons of gold, rare jewels and priceless art hidden by the Nazis in a secret labyrinth of tunnels. When 2015 two treasure hunters claimed that they had located "Hitler's Gold Train" in the area of Walbrzych, the news made headlines all over the world. But what is the truth behind the alleged discovery? This documentary is looking for answers.