Guy Fletcher is an actor who overhears a joke about his mother, a famous and much loved actress (very few people know he is her son).

His only lead, a company called Sphinx that apparently makes vacuum cleaners, is where one of the joke's trails ended.

He puts them in cells and, reveals that Sphinx creates and distributes jokes so that people will not take things, like politics, too seriously.

Maintenance had not addressed the flaw because they were short staffed, causing Liddy to shout out the punchline of the book 'How many top-secret government technicians does it take to change a light bulb?'

The penultimate chapter of the book describes with intentional clumsiness how Guy and Sally went to France to start a new life.

Denise Pickles of Reviewing the Evidence said while The Killing Joke was sometimes confusing, the book altogether was interesting.