They’re the kind of visitors one is least prepared for and never wants to have. The front door opens — of your office early one morning, or your home late one night — and a big guy leans down and holds out a badge. “The name’s Goliath, FBI.” Another guy quickly follows with the same routine: “Kong, special agent, Internal Revenue Service. We’ve got search warrants, and we’re coming in.”

So begins the saga of the unfortunate white-collar professional who comes under the scrutiny of the federal government. Federal agents swoop down with the force and will of the proverbial giant — or at least it feels that way to the person being swooped upon.