Maths-whizz Alice has already solved a mystery or two Persuaded by wannabe sidekick Sammy to investigate a scientist's disappearance she's soon entangled in her trickiest case yet Dr Learner is reputed to have invented an invisibility suit but is whacky science really to blame for his vanishing? With the unlikely help of erstwhile nemesis Kevin Alice solves the puzzle
- only to face another Should she reveal the truth or protect her most devoted friend?