He has the air of a rockstar who decided to hang up his guitar and pick up the pen instead. He knows that you will hang onto every word he says because of what he is talking about - Jack the Ripper.
Hollywood buffs might recognise Bruce Robinson from Withnail and I. You might also remember him as the director of Johnny-Depp starrer The Rum Diary.
But for now, he is all about his 800-pages plus magnum opus that took 15 years of research - They All Love Jack: Busting the Ripper.
Robinson believes he had nailed the real Ripper - a man called Michael Maybrick - as he brushes aside innumerable speculations by Ripperologists and the Freemasonologists. And why does Robinson think Maybrick is the man? You'll need to read the book to find out.
We spoke to Robinson about the phenomenon of serial killers, psychological profiling of these killers, the Freemasons, and Jack The Ripper - a 'misogynist' who let his Id (defined as 'the disorganised part of the personality structure that contains a human's basic, instinctual drives') run amok in 19th Century Britain, and made a permanent place for himself in criminal history.