Horatio and Delko travel to Rio to find that Riaz, the man responsible for Marisol's murder, has been released from custody. While there, Horatio meets Yelina and learns that his brother may be connected to Riaz. Meanwhile Ray Jnr. accepts work from Riaz to mule drugs to Miami, unaware of the recent death of his father. Riaz is finally found in Rio, and dies in a knife-fight with Delko and Caine. Back in Miami, Natalia, now a CSI, helps Ryan investigate the beating death of a woman, and her inexperience leads to problems for Calleigh in the office. Caine, now also back in Miami, manages to track down and rescue his nephew.