Asked by a Swiss banker to investigate a series of bank robberies committed by dogs, young detectives Max and Maddy Twist travel to Switzerland, where they disc

Max and Maddy and the Chocolate Money Mystery

When a famous millionaire asks young detectives Max and Maddy Twist to investigate who is sabotaging an international balloon race for charity, they find themse

Akimbo goes to the rescue of a zoologist who is injured on his father's game preserve.

Harriet helps her detective aunts, Thessalonika and Japonica, investigate cheating at the racetrack by disguising herself as a jockey. Reprint.