There was a bomb attempt on Hitler's life in '39, and only missed killing him because it was on a timer and he unexpectedly ended his speech 10 minutes early.
I know, but there were several attempts on Hitler's life during the course of the war. The last bomb attempt was in 44. It almost got him. Afterwards, Hitler had 200 people executed because of it.
Not that Wikipedia is the sine qua non of unbiased info, but: http://en.wikipedia.org/wiki/July_20_Plot