Horatio is approached by a parolee he helped put away several years ago, who begs for his assistance in finding his missing teenage son. As the investigation gets underway, Horatio discovers that the boy may be planning a deadly assault at his high school. Meanwhile, as Speedle investigates a man's death, the victim's flirtatious girlfriend, who was there when he died, tries to play on Speedle's obvious attraction to her.

A woman is killed during a posh party at an exclusive waterfront estate when a man opens fire on the proceedings from a cigarette boat. When a former con is arrested, he acts as his own lawyer and proves to be smarter than he appears. Complicating matters is the fact that the leading witness in the case is the dead woman's 10-year-old son, whom Horatio wants to protect, refusing to let him testify.

The wife of a famous baseball player is brutally killed in her home and her philandering husband is charged with the crime. The jury on the case, as well as the accused and his defense, visits the house to examine the crime scene, but when the lights are dimmed, as they were when the victim was killed, and then turned back on, the ball player is found dead with a meat clever in his back and a note that reads "guilty." Now, as Horatio and the team find that the husband's defense team tampered with the crime scene, they must examine the evidence to find the couple's killers. Meanwhile, Horatio gets a call from Yelina, who tells him that her son, Ray, Jr., is missing.

Evidence leads the CSIs to believe that someone started a massive fire in the Everglades in order to cover up a murder. Local prisoners are brought in as free manpower to help fight the wild fire in the Everglades. However, when a serial killer escapes the scene, Horatio must track him down before he strikes again. Meanwhile, the body of a local college student is found shot to death and the fire has destroyed the crime scene and the evidence. However, when the team uncovers an illegal moonshine operation and homemade ammunitions in the vicinity, the CSIs uncover the real reason why the boy was out there.

An axe murderer on death row is given a stay of execution just moments before it was to take place, on the grounds that there may have been tainted DNA analysis used at his trial. Now, without using any DNA evidence, the team must race against time and reexamine all of the physical evidence in the case, just as they get a call on a new double murder that looks suspiciously like the case they're working on.

The episode picks up straight where "One of Our Own" left off. Horatio and Delko have arrived in Rio de Janeiro to hunt down Antonio Riaz, who ordered the hit on Marisol. The problem is that Horatio can't stop thinking about his late wife, and Brazilian authorities aren't being very cooperative. While there, Horatio runs into Yelina and finds out that Raymond is missing again. Ray Jr., now fourteen, teams up with Brazilian authorities and will stop at nothing to bring his father home safe, until Horatio learns the terrible truth... Raymond is already dead. Now Horatio must stop his nephew from getting himself killed trying to chase a ghost.