Horatio investigates the murder of a model intentionally run down outside of a Miami hotel by a driver who fled the scene. When the evidence leads to a suspect, governmental red tape puts an unexpected twist on the proceedings. Horatio and Yelina begin to confront their feelings for one another.

Horatio hunts for the person responsible for a vicious attack on a woman who was lured to a vacant condo and beaten with a piece of lumber.

A man and his wife are trying to drive out of a hurricane's fury when they strike and kill a man in the blinding storm. Horatio finds that the lack of impact wounds on the victim's knees suggest that he struck the car as opposed to the car striking him. Meanwhile, in a seemingly unrelated case, Horatio finds another victim of the hurricane impaled on a fence. However, as the CSIs uncover the scattered remains of the post-storm evidence, it seems that these two cases may have a deadly connection. Meanwhile, after Calleigh witnesses a man looting a house, she realizes that she's got another case on her hands when she finds his ex-wife inside shot to death.

Horatio is driven to find his brother's killer and protect the niece he never knew existed when a woman shows up with Ray's illegitimate child. The team explores a voyeuristic Internet site in connection with a stockbroker's murder.

A young woman is thrown over the railing of a parking garage, but the investigation into her death uncovers evidence that she was killed before the fall and had likely been kidnapped. The victim's watch is traced to her boyfriend, who tells the detectives that she was a thrill seeker who was abducted during the course of an extreme kind of role-playing game. Meanwhile, Delko gets into trouble when he inadvertently interferes with a case after stumbling across a car-theft ring.

A cigarmaker is found in his store tied up, beaten, mutilated, and murdered with a chaveta, a cigar-making tool featuring a rounded blade. The investigation leads Horatio to a group that helps Cuban refugees. Across town, a 25-year-old man is gunned down while withdrawing money from an ATM, but the motive doesn't appear to be robbery since the cash he withdrew is left behind.

Delko and Alexx are nearly burned alive when they investigate the death of a hunter found shot near a supposedly controlled burn in the Everglades. The fire suddenly rages out of control and traps them, forcing them to take refuge under a tarpaulin. Later, a second body is discovered, and this time it's a young woman who looks to have been beaten to death. After bite marks are found on the victim's breasts, Horatio is led to believe a sex offender is behind the attack – and the fire.

When a former surf champion is murdered in his home, the CSIs are determined to find the killer. Ted Henderson is killed in his own home and his body is missing, while his wife and son are left beaten and bound. While searching the home, Horatio finds heroin in the son's room and learns that he is secretly a drug dealer. Meanwhile, the CSIs find a home pregnancy kit in the bathroom that reveals Ted's wife is pregnant, but Alexx finds proof that the baby could not possibly be Ted's. Now, Horatio and the team find evidence that suggests that someone at Ted's surfboard manufacturing plant was not only the son's supplier, but may have a strong motive for the murder as well.

A police officer collapses and dies after pulling over a car, and the investigation reveals he was murdered. Horatio grows suspicious when Internal Affairs gets involved in the case, leading him to believe that the killing wasn't a random crime. Meanwhile, Calleigh aids an abused woman who is living with one of the suspects in the probe. Yelina begins dating Horatio's nemesis – who is heading up the Internal Affairs inquiry.

An adult film actress is found strangled in the park and the CSIs must find the killer. Blood and human tissue are found under Ashley Anders' nails and the DNA matches that of the CEO of the company that distributes her films – and he's a registered sex offender. Also, Calleigh discovers his answering machine audiotape on which he makes a threat against Ashley. However, there is an accident back at the lab with this crucial piece of evidence and Delko was the last person to handle it. Now, IAB's Rick Stetler is put on the case, much to Horatio's dismay, as the CSIs try to uncover further evidence in order to find the girl's killer.

After a large yacht slams into a major Miami bridge, the team finds that the man steering the boat was shot and killed before the accident. The victim's wife reveals that their son had been kidnapped and her husband was handing over the ransom – three million dollars worth of jewels. But when the team learns that the jewels were fake, the investigation leads them into a dangerous situation at a jewelry shop that may contain crucial evidence, where Horatio must face the unimaginable when one of the team is killed in the line of duty.

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 CSIs must find the killer after a young woman is pushed in front of a moving bus. Alexx finds a bruise shaped like a hand imprint on the victim's back, proving that she was pushed in front of the bus, and her boyfriend, Jay Seaver, is the prime suspect. When one of Jay's office rivals also turns up dead, Jay reveals that he has a psychotic stalker, Claudia, who he thinks might kill to please him. However, when Jay hires a lawyer to protect Claudia, Horatio suspects that Jay may be more involved than they thought. Later, a man's body is discovered down an elevator shaft in a nearby building, and there is evidence to link the victims to a common killer. Meanwhile, Calleigh's father seeks her help when he fears that he may have killed someone after a night of drinking, and Horatio assigns a new CSI, Ryan Wolfe, to the case.

E-mails and text messages trigger a mass gathering of students to perform a random task on a golf course. However, as the crowd disperses, the body of a high school student is found. The original message triggering the "flash mob" is traced to a high school senior whose father is a high-powered defense attorney. The case changes direction when Horatio and the team learn that the schoolmaster's daughter may have had something to do with the murder and evidence reveals that the victim was having an affair with his chemistry teacher.

An 18-year-old girl is stabbed to death in a bathroom of a popular Miami nightclub. Horatio learns that the victim was an investigative aide working for Alcohol Beverage Control and was monitoring underage drinking. As Horatio interviews the club's owner, an unknown man drives by the club, sees that the police are there, and crashes his car while fleeing the scene. However, the case gets more complicated when they discover another murdered victim inside the car. DNA from the second victim's watch ultimately leads them to a day spa where the services may not be entirely legal. Meanwhile, Calleigh and Ryan work together to determine whether an insecure and underage teenager at the club that night had anything to do with the murder.

As a huge tsunami heads directly towards Miami, a ten-hour warning gives citizens just enough time to evacuate the city. In the chaos, two people are killed in a parking lot and the evidence leads Horatio to discover a plot to rob a bank timed to take advantage of the evacuation. However, as the CSIs close in on the robbery already in progress, they find that it's a more elaborate crime than they previously thought. In the wake of the storm, Ryan and Alexx discover a body washed up from a local cemetery that may have a different cause of death than originally recorded. Meanwhile, Horatio suspects that Yelina is being physically abused by her boyfriend, IAB's Rick Stetler.

A murder investigation takes Horatio and the team into the world of speed dating. Richard Laken is found killed by a tire iron outside a lounge following an evening of speed-dating. The team discovers his car is covered with acetone, which traces back to one of the female guests. She reveals that she dated Laken and he dumped her, so she doused his car with nail polish remover for revenge, but she didn't kill him. Now, when Horatio and the team learn that Laken recently witnessed a serious assault at a Miami Heat basketball game, they are on the hunt for two perps instead of one.

The team investigates a modern-day piracy off the coast of Miami after six bodies are discovered floating in the ocean tied together by rope. Horatio suspects that a ship was hijacked with some of the crew killed and then dumped overboard. Evidence suggests that other crew members might have escaped on a life raft. Using radar and GPS technology, the CSIs find survivors but their stories don't match. Now, Horatio and the team must learn what really happened out in the ocean as they find themselves investigating the seamy underbelly of Miami's militias and arms dealers.

The CSIs must investigate when a pedestrian is killed after a man falls from a building and lands on him. Horatio and the team find that the victim found on the sidewalk is not the same man who fell from the building, but the unfortunate person he landed on. The CSIs discover that the fallen victim is in possession of a sex DVD involving a top Miami criminal judge and a woman with a sordid sex life. When the woman is found dead, the team must delve into the complicated personal lives of those in Miami's judicial system in order to find the killer.

When a woman is killed in what looks like a carjacking, the CSIs talk to her husband, the oldest of the three brothers who run their lucrative family business. However, when it is revealed that the victim had a gambling addiction that could have bankrupted the company, the team must follow the evidence to find the killer. Meanwhile, Alexx hires a recovering alcoholic as a body hauler and must investigate when he is accused of stealing from the dead.

When gang-related gunplay goes down in an emergency room, Horatio and the team must find the gang members responsible. The evidence suggests that an orderly in the hospital recognized the wounded gang member, who possibly killed one of the orderly's friends and alerted gang members to his location. However, the evidence doesn't match up and the CSIs discover that a cheating girlfriend, not gang retaliation, may be behind the shooting. Meanwhile, Ryan questions a mother in the emergency room after her story regarding her child doesn't add up.

The CSIs uncover a complex counterfeiting operation after a bellboy is found murdered at one of Miami's hottest hotels. The luggage that the deceased bellboy had been loading, as well as a heist of a special paper that money is printed on, leads the CSIs to uncover a complex counterfeiting operation. It's cruise season in Miami, which means that the population of Miami swells, giving the team even more suspects to the murder. Meanwhile, Calleigh must investigate when a woman goes missing, and is later found dead, after she and her husband attend a hot and flirty "friction" party.

When the CSIs find a woman swallowed whole and killed by a gigantic snake, they uncover a covert drug smuggling operation. Evidence leads Horatio and the team to a drug smuggling operation where large snakes are suspected of be being used to bring illegal drugs into the country to avoid detection by customs. However, when Horatio finds that Clavo Cruz, a nemesis of Horatio's who hides behind his diplomatic immunity, may be behind the operation, the team must find a legal way to put the criminal behind bars. Meanwhile, Wolfe must find the truth when two women each claim that they are the real victim of identity theft and the other is the culprit.

Someone uses a laser light to blind a pilot and bring down a jet, which carries $1.2 billion in checks to be delivered to banks on the eastern seaboard. The crime scene evidence reveals a victim, a young fundraising socialite, who was inside the plane but killed prior to the crash. Now, although the team has little to work with since the victim's wealthy family is opposing an autopsy, Horatio must follow the money trail. Meanwhile, Calleigh works on the case with her ex-boyfriend, Detective Hagen, and their romantic history could cause problems for both of them.

An extreme skateboarder and videogame tester is found dead on a half-pipe platform used to program extreme skateboarding video games. The CSIs discover that he was wearing reflective sensors when he was killed, so the motion-capture device used to produce these videogames recorded the murder as it happened, but not the murderer. Now the team delves into the highly competitive world of videogame programmers and testers to find the killer.

Horatio's life is changed forever when he learns important information about his deceased brother. Horatio must now figure out what to do with this information about his brother, Raymond, and whether or not to tell Yelina. Meanwhile, the team investigates when a woman is murdered at a crowded bar after she's approached by a female employee of a service that helps men pick-up women. Also, when Delko loses his badge after some reckless behavior and it's used in a crime, he must locate the badge before it's used again.

The team must find the connection between the two crime scenes; the killing of a drug dealer and the rape of a well-off family member.

The team investigates the death of a foreign exchange student, the search for two missing teenagers, and the robbery of 10 million dollars in golden bars.

The search of a missing 17-year-old girl, whose trip to Miami turns into an ongoing nightmare.

Horatio and the team are trying to figure out how to free an innocent young man after a harsh interrogation with Frank Tripp sends him to jail.

Three suburban housewives on a girls' weekend in Miami are the prime suspects when the hotel's handsome pool boy is found murdered. When Horatio is tipped off that his team is facing a surprise efficiency review, he must trust Calleigh, Delko and Ryan to work together to find the killer. However, when they independently follow the evidence, each discovers that their analysis points to a different killer.

The CSIs must race against time when all evidence in a murder case points to Horatio. When a murdered woman is discovered, Horatio admits that he was seeing her and that he was the last person to see her alive. Although the evidence logically points to Horatio as the killer, our CSIs must now dig deeper to find the real killer and learn who would have the motive and the method to frame him.

A drug lord is gunned in his Coconut Grove mansion and a suspect arrested at the scene claims he sells marijuana to Delko. Stetler, from Internal Affairs, investigates and the case quickly gets personal when Horatio gets involved. As for the shooting, the CSIs learn that two gunmen may have been involved. Also, Calleigh makes a major decision concerning her job.

The CSIs investigate the brutal murder of a man who was learning how to pick up women at a hot nightclub. Meanwhile, Horatio tries to help out Marisol, Eric Delko's sister, who was arrested on drug charges.

When evidence shows that a series of murders is linked to organized crime, Horatio and the team are instead lead to a pair of film students who have screenplay that contains the details of the crimes.

When Horatio's nemesis, Walter Resden targets someone close to him, Horatio tries to stop him. Also Eric Delko's relationship with Natalia is tested when she thinks she may be pregnant.

After a man is found not guilty of his wife's murder the CSI team finds evidence to the contrary.

After a group of wealthy women are robbed at a luxury day spa, evidence leads the CSIs to believe that this is a part of a much larger car chopping scam and each of these women are being targeted for a home robbery. Matters become worse when Horatio discovers that Marisol was also at the spa during robbery and he must now protect her when her life is threatened. Meanwhile, Ryan must deal with the fallout after he freezes during a shootout.

The CSI team must locate a woman who has been kidnapped and dialed a wrong number on her cell phone. To try and find the woman the team must first figure out whom the kidnapped woman was trying to call in the first place. Marisol has a difficult decision to make and Horatio helps her. Natalia is surprised when Ryan asks for Delko's permission to take her out on a date.

A cruise ship that is docked in Miami is the scene for a double murder. The team investigates the long list of potential suspects but soon find that the list is dramatically decreased when the CSI's find a large amount of money is missing from the victim's stateroom. Horatio and Marisol's relationship evolves.

The Mala Noche gang trial is obstructed when the defendant goes free with the help of the witness who is testifying. When a hit ordered by the Mala Noche gang on Horatio finds the people he loves lives are in danger. Delko finds that an ex-lover is disturbing any woman who he is now close to.

In this thrilling season finale, the loss of one of their own is the first hit the lab will take. Getting back to the lab to process the evidence, they find it has been taken over by Federal Agents looking for stolen money from a previous case.

The CSI’s investigate the murder of a male model and have to figure out the inner workings of the modeling world in order to find his killer.

The body of a local politician is found in an empty house. The entire neighborhood was upset that he was backing the use of eminent domain, allowing the government to force them out of their homes.

When strange accidents occur in the lab, the CSI team is spooked during a death investigation involving voodoo. As Halloween is near everyone starts to think that the lab is cursed.

After an accident where the driver was decapitated during a dangerous stunt, the evidence leads the CSI’s to believe it was more than an accident. While gathering the evidence, the CSI’s find they must go into the world of “sideshows.”

A murder and kidnapping becomes personal when DNA from a crime scene reveals that Natalia’s sister Anya is one of the kidnapped women they are looking for. The team finds a safe full of photos of missing women and they must find the photographer who was using his camera to lure the unsuspecting women.

A Marine recruiter is found dead on a civilian shooting range with various bullet holes in him, but there is no blood at the scene. The investigators uncover that the victim was dead before he was shot and that his body was pulled onto the range. As the case advances, Horatio determines the murder may be tied to the death of a marine in Iraq who was killed in combat. Likewise, Natalia is shocked to learn that Nick asked Valera out and that she accepted.

When terror suspect Sonya Barak is targeted by her own people for assassination, she goes on the run, and Horatio sets out to capture her, both to protect her and bring her to justice.

After Nick is found to have been killed with all the evidence pointing to Natalia as the killer the rest of the team has been sidelined by the Internal Affairs investigation. Horatio with the help of the night shift lab and Calleigh’s ex-boyfriend have to find the evidence to clear Natalia.

Horatio has Eric rushed to the hospital and watches as the doctors try to revive him. The rest of the CSI team finds evidence that may lead them to Cruz.

After a wealthy businessman is killed at a charity event the CSI's first suspect his wife who was hosting the event. The blood evidence is thought to belong to the wife or her two secret twin sisters but leads the investigators in another direction after the victim is not who they thought he was.

When one of Horatio's team lets their personal problems contaminate the investigation involving a spurned ex-lover, Horatio has to fire that team member.

When the team is investigating the murder of a probation officer and a hostage situation, Horatio learns that the main suspect could be his son.