When the NCIS team engages in Walk-a-Mile day to gain a new perspectives on different departments, things take a turn when Kasie receives a distress call from a mysterious man.

With the help of Knight's dad, Special Agent in Charge Feng Zhao, NCIS works to unravel the mystery of a recently used service weapon belonging to a missing agent. Also, McGee is in a tailspin when DNA results reveal a close relative he was unaware of.