When three masked assailants invade a home and murder an entire family, including a pregnant woman, the CSIs are called to the scene to investigate. Catherine leads the team through the emotional case, which intensifies her own longing to reconnect with her estranged daughter, Lindsey.

The CSIs investigate the murder of a dominatrix found near her secret sex dungeon.

The CSI team investigates after a group of teens discover a dead woman behind the wheel of an abandoned car in a Nevada ghost town.

A mysterious bigfoot-like footprint found near a crime scene puzzles the CSI team as they work to uncover who - or what - killed a father and son.

Max leads her team to investigate the death of a prestigious Michelin-starred chef found hanging in his restaurant’s walk-in freezer.

Catherine’s day off with her granddaughter gets interrupted when a woman wakes up from a four-year coma and remembers details from the night her sister died.

The CSI team investigates a bomb that detonated during a masquerade party for wealthy investors at the site of a new casino.

When wrongly accused former suspect Gene Farrow enters the Crime Lab covered in blood, wielding a cleaver and looking for Allie Rajan, the CSI team investigates his peculiar story about a macabre party with a fatal ending.

The CSI team investigates a case where an ambitious investigative reporter is found dead at a peanut factory. Also, everyone in the crime lab buzzes over who Max will promote to day shift supervisor.

As Halloween descends on Sin City, the CSIs investigate when a creepy mannequin prop inside a popular haunted house turns out to be a real dead body. Also, Catherine enlists the help of Folsom to search for her friend who disappeared.

After all the guests attending an upscale fundraising soiree for the science department at a local university fall ill, the CSI team gears up to investigate. Also, Catherine enlists Grace’s roommate to help her find clues after Grace disappears.

The CSI team investigates the death of an archaeologist found near the breakthrough discovery of an ancient civilization. Also, Max locates another cryptic note written in familiar silver ink after a mentally distressed woman kills her attacker.

The CSI team investigates a murder case that hits close to home for Folsom. When he is forced to sit this investigation out, he does his own digging with help from Trey. Worried Folsom will do something he regrets if he gets his hands on the killer, the team find themselves racing to arrest the suspect first.

With a new piece of evidence at play, Catherine Willows reopens an investigation from her past that never got solved after a violent attack left her hospitalized. Internal affairs begins questioning Folsom.

The CSI team is called to investigate when the bodies of Frank Sinatra and Joey Bishop impersonators are discovered behind the drywall of a home construction project. Also, Folsom must face the review board about the future of his career.

Grissom and Sara's investigation into charges against David Hodges heats up as Internal Affairs joins the hunt. Also, pressure rises for the CSIs when a video game developer's body is found floating in a fountain before a huge gaming tournament.

The CSI team investigates when a body is dug up in the luau pit of a Hawaiian-themed hotel. Also, Internal Affairs begins to question Grissom and Sara's return to the crime lab.

As Grissom and Sara close in on who framed Hodges, the CSI team investigates a lock room murder mystery at 30,000 feet, when a cargo plane lands autonomously at McCarran Airport and everyone on board has been killed.

An abandoned horse covered in blood leads the CSI team to a halfway house for convicted murderers. Also, Grissom and Sara begin to circle their prime suspect in the David Hodges case.

Catherine’s frustration intensifies when a lead suspect in Grace’s disappearance is found murdered. The team exhausts all their skills to figure out who killed the suspect, and if his death will lead them to Grace.

When the bodies of two Regency Romantic Festival attendees are discovered, the CSI team uncovers a shocking link between their murders and previous cases.

The CSIs investigate the mysterious death of a competitive eating contestant, and Chavez partners with Allie to prove where the mysterious silver ink notes have been coming from.

With their respected colleague Josh Folsom under arrest for the death of Kahn Schefter – the man responsible for killing Folsom’s mother – the CSI team combs through every crumb of forensic evidence to determine his innocence or guilt.

When a mechanic is found murdered in a dark factory, the CSI team investigates whether the perpetrator was human or a humanoid robot with an AI operating system.

An attack on Jim Brass kicks off a twisted conspiracy targeting the Las Vegas crime lab.