Renata has the nickname Wolfie because she's a lone wolf who is more interested in nonfiction books than she is in people. Friends just get in the way of what she wants to do! One afternoon while she is building a submarine out of an old refrigerator box, a neighbor boy nicknamed Flu (he always buzzes around annoying people) knocks on her door. Together they go on an amazing adventure in the submarine that teaches Renata about pretending and friendship.

The text is amusing and easy to read for kids who want to read beginning chapter books. Both Wolfie and Fly are interesting and charming in their own ways. The book illustrates how powerful pretending can be, but also has a delightful twist showing that the water is not completely imaginary. Neither the reader or the characters are completely sure of what is pretend and what is not. This is an excellent choice for young readers who are looking for easy, short chapter books, and readers will look forward to more books in the series so they can have more adventures with Wolfie and Fly.