" There was a beat of silence and the atmosphere thickened briefly. I glanced from one of them to the other, seeming to detect an invisible something passing between them, not so much a signal as a sort of silent token, like one of those almost impalpable acknowledgements that adulterers exchange when they are in company. The phenomenon was strange to me still but would become increasingly familiar the deep I penetrated into the secret world. "

― John Banville , The Untouchable