Ep 2. Impact

Hetty sends the NCIS team to investigate a mysterious man who visited a naval research laboratory. While finding out the man's true identity, the team discovers a strange substance that could potentially threaten national security. The team soon comes under attack, and they must fight their way out of danger and prevent the substance from falling into the wrong hands. Along the way, the team also deals with personal issues, including Kensi's recovery from her injuries and Sam's struggles to balance work with taking care of his family. Through it all, the NCIS team works together to save the day and protect the country from harm.