Lively, curious James creates a stinky, scary concoction from spices, juices, and hand lotion. He has no idea how much trouble he's caused.
Some of the mixture spills on his purple chewed gum. The gum grows and James can't stop it. Much adventure follows. He watches his family and neighborhood become frantic.
Newspaper and television reporters disrupt their lives. James' friends add to the humorous action in their pursuit of fame. James does not want to be famous. He's upset because he's not sure what he did.
When the growing gum becomes local news, James is kidnapped. His dog, Chip, and his sister, Ann, become heroes. James worries he's started something dangerous that is unstoppable. He gains a new understanding and appreciation for responsibility and knowledge.
