This dark sense of drama has an interesting effect on your fellow diners. Instead of the perfectly respectable denizens of St John's Wood they most likely are, you begin to imagine them as protagonists in a series of febrile vignettes: the three, suited, middle-aged chaps in the corner were clearly members of a powerful, corporate sect; the pleasant, soignèe woman opposite was quite evidently softening up her elderly companion before administering the final dose of untraceable venom.