Like her classmates Iggy Peck and Rosie Revere, Ada Twist has always been hopelessly curious. Why are there pointy things stuck to a rose? Why are there hairs growing inside your nose? She embarks on fact-finding missions and conducts scientific experiments, all in the name of discovery. When her house fills with a horrific, toe-curling smell, Ada knows it s up to her to find the source. But, this time, her experiments lead to trouble.