The deadly dungeon: While visiting Wallis's castle, Dink and his friends investigate strange noises that lead them to a dangerous secret. The empty envelope: Dink and his friends unearth the mysterious truth behind the envelopes incorrectly delivered to his house. The falcon's feathers: Josh and his two friends look for the person who stole a peregrine falcon from its nest. The goose's gold: When Ruth Rose and her friends, vacationing in Florida, discover that her grandmother is about to invest in a project to recover sunken treasure, they stumble upon evidence that the entire plan may be a fraud.