After winning the National STEM Championships, Kensy, Max and a team of students from Central London Free School are ready to compete for the international trophy in Singapore. But when Granny Cordelia is poisoned, the twins no longer feel like celebrating.

They still have a duty to their team though, and everyone seems to think they'll be safe in a country halfway around the world. It turns out that Singapore is rife with mysteries. Soon Kensy and Max have uncovered a much larger case than anyone counted on. And this time, it's personal.