The puzzles are set in a larger story of a mathematical detective named Dr. Ecco, his nephew and niece, and Professor Scarlet, the narrator. Scarlet is essentially the Watson to Dr. Ecco's Sherlock Holmes, asking the questions a reader might ask. Each puzzle is posed in a plausible if imaginary real-life setting. There are no hidden facts, no abduction here, just deductive logic and mathematical thought.
Overlaying these puzzles are the ramblings of Dr Ecco's old nemesis, Benjamin Baskerhound. He seems to be on the run, but he's trying to tell Ecco his whereabouts in a way that only Ecco will understand. The evidence builds up and readers are invited to send in their solutions. The winner will receive a pre-paid trip to the home of modern mathematics, Sir Isaac Newton's Greenwich Observatory.