When Dr. Alicia Seberg, a government research scientist (guest star Amy Price-Francis), is exposed to a deadly toxin while at work and has only hours to live, she calls Patrick Jane and the CBI to find her murderer.
The NCIS team races to solve the murder of a Marine by an exploding cell phone and to find the remaining men of his former EOD (explosive ordnance disposal) unit before another deadly explosion kills someone else.
Zack can't hide his jealousy when Billie starts dating another guy.