Nancy, Bess, and Georges Jiu-Jitsu lessons turn into a takedown of another sort in the twenty-first book in the Nancy Drew Diaries, a fresh approach to a classic series.

After a close call, Mr. Drew insists that if Nancys going to be an amateur detective, she needs to be able to defend herself. So Nancy, Bess, and George decide to check out a Jiu-Jitsu class at Iron Dragon MMA. The technique is hard, but before she knows it, Nancys having a lot of fun.

And then, just as class ends, the students are shaken by a disturbing sightsomeones left a dead rat on the front desk and spray-painted traitor on the wall. With a big competition coming up soon, is a rival academy trying to stir up trouble to throw the Iron Dragon team off their game?

Nancy agrees to help the team get to the truth, but as her investigation takes some unexpected and increasingly dangerous turns, has River Heightss finest sleuth been outmatched?