NCIS: Los Angeles - Disorder

Star Trek The Next Generation's Jonathan "William Riker" Frakes directs and has a spot guest star role in this episode of NCIS: Los Angeles as a psychiatrist who has to assess an ex-navy officer suffering from Post Traumatic Stress Disorder.  The ex-officer was a witness to a shooting where there were two deceased.  What's the real story and what effect is this going to have on the team as they try to protect the ex-officer from possible Iraqi terrorists. 
This was the Christmas episode where Hetty re-gifted previous gifts back to the team.  A solid episode that kept you guessing.