you can get the documentary on dvd, its called
HITLER'S LOST SUB.
it's two hours long.
narrated by Roy 'Jaws' Schieder.
i got mine from Amazon.
i wont tell you any more - cuz it will spoil it for you.
though i must say, the book is a crackin' page turner. i didnt stop reading it - literally, i read will i cooked i read it on the way to work - at work, on the loo, while the kettle boiled, as i fell asleep - and picked it up again in the morning....
does this sell it !!
