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.