In Linden, California one plucky teen masterminded a locker room sting operation only to find out her much-loved, 30-year-veteran gym teacher had been stealing money from students.

Linden High School sophomore Justine Betti told KXTV that she had to do something after she and her fellow students noticed money had been disappearing from their backpacks all year. One day during gym class, Betti stayed behind after her peers left, stuffed herself into one of the lockers and caught her teacher rummaging through her fellow students' belongings. "Something needed to be done," Betti told the local ABC affiliate outside of Stockton, California. "That’s not okay."

So she returned to her locker/hiding place, this time with a camera in tow (or her cellphone, rather). In an operation that would have made Agent Carrie Mathison proud, Betti set up a second camera to record from another locker. The video she captured the second time around shows a teacher rummaging through backpacks and eventually taking something out of a pink duffel bag.

But when she brought the video to her principal he tried to snuff out the independent investigation. "He said that he’ll investigate it and he told us to delete the video, but I had already sent it to my dad,” Betti told the local news. For now, the unnamed teacher is on administrative leave while the school district launches their own probe. For her part, Betti says it was a tough decision to call out the well-regarded teacher, but everyone thinks she did the right thing.