We all have them. What gets on your nerves? Excessive technical detail in thrillers Why is it a gun never a gun, or a helicopter never a helicopter? Why must the author tell us the make, defining feature, what special covert force (which will, of course, be the most accomplished in the world) it is used by, rate of fire and all manor of details plagiarized from guns and ammo? All knowing character, often in the form of wise old mentor dude You know the type. The guy who knows exactly what is going on but refuses to tell our hero’s anything mumbling words to the effect of “you are not ready” or “when the time is right”. Bonus demerit points if the author kills them off just before they are about to reveal what they know thus allowing the series to be stretched out for several more books.