Melissa Lane, Girl Detective, must solve a crime of stolen lunch money with her two helpers.
The Head Mistress, Mrs. Inverarity, tries to stop her because Melissa might embarrass the School. She works through the clues and suspects in a professional way until she discovers the truth, with the help of two friends.
But the culprits surprise everyone with the reason the money was stolen. In the process Melissa also solves another problem.
