A former FBI subcontractor guns down an agent inside the agency's headquarters and takes a member of Don's team hostage. Charlie and Alan, who are visiting the FBI office, assist in resolving the situation. Megan and Liz take to the field to learn more about the hostage taker.
![Numb3rs S04E10 - chinese box [HDTV, XviD]](http://img223.imageshack.us/img223/6233/numb3rsxf3.jpg)
