The team must locate a classified device with the power to destroy Los Angeles that was stolen from a college research facility. Meanwhile, Sam tries to track down a highly sought-after Christmas present for his daughter.
Mac and Danny investigate the death of a woman found dead in a bathtub filled to the brim with rose petals. Meanwhile, Stella probes the death of a young man who fell face first into the fish tank in his penthouse apartment.
Catherine and Vartann stake out a hotel room narcotics lab, while the discovery of a woman's body leads Ray and Nick into a murky underground fetish scene.
The cyber team investigates after the dispatch software of a car service is hacked in order to target specific passengers.
Vacationing on a remote Caribbean island, unarmed Tubbs is the target of vengeful drug kingpin Orlando Calderone.