Danny and Baez investigate when a stray bullet strikes an elderly woman in her home. Frank reprimands another cop for smoking on the beat.
When Sherlock and Kitty investigate the murder of a small postal store's owner, they discover a connection to the illegal diamond trade.
Reese and Finch are sent to a wedding to protect a pair of POIs. Fusco takes it upon himself to investigate a series of missing person reports.
Henry and Jo investigate the death of a financial investment expert who turns out to be the son of one of Abe's friends, and Henry recalls his anxiety over letting Abe go to Vietnam.
When a young heiress dies of an apparent drug overdose, Lupo and Bernard begin to suspect her cousin, whose inheritance increased after her death.