It was dark and gloomy when we returned at midnight to the sandy channel below the place where the Crown of Thorns starfish had appeared on the coral reef above.
Some light filtered down from the moon and starlight, so we could come pretty close to the place where our undercover agent had buried himself in the sand.
I carefully and quietly knocked our agreed upon code on the sand: "Knock, knock-a knock, knock--knock, knock."
"Who's THERE?" asked a sinister, quiet, and very unfamiliar voice from above.