Beware the gleam in Uncle Fred's eye

Lord Ickenham nodded brightly.  There had come into his eyes a gleam which Pongo had no difficulty recognizing.  He had observed it on several previous occasions, notably during that visit to the Dog Races just before his uncle's behavior had attracted the attention of the police.  He could read its message.  It meant that some pleasing inspiration had floated into Lord Ickenham's mind, and it caused a shudder to pass through his frame, together with a wish that he were far away.  When pleasing inspirations floated into Lord Ickenham's mind, the prudent man made for the nearest bombproof shelter.

---from Uncle Fred in the Springtime by P.G. Wodehouse.