Maia misses the big race with her friend Fig because she is too busy playing with the mermaid she met swimming in the local pond. Fig can't see the mermaid, and is sure Maia is making stuff up. The two quarrel until Maia brings a jar of purple goo that her aunt made. Fig tastes it. It's the worst stuff she has ever tasted. She throws the jar into the lake. But she does, briefly glimpse the mermaid, Trezzie. Now she believes her friend.

Having an imaginary friend can be confusing. The child who has this friend sees and hears this playmate, just like all the others. But when the child talks about this friend, nobody believes the stories. And the friend is never there when the child wants to introduce him or her. This sweet story shows both the real friendship and the frustration of not being believed.