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.

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.

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

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

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 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.

Medical examiner Sonya's life is in jeopardy when she is exposed to a mysterious poison as the CSI team races to find the antidote and the silver ink murderer who appears to be targeting the Crime Lab. Max's ex-husband, Daniel, returns to make sure that she and their son are safe.

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.

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.

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.

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.

The CSI team investigates the death of a local antique shop owner who died from an apparent gunshot wound that is missing one important clue - the bullet. Also, Max makes an important breakthrough in the ongoing case with Ocho from the robotics factory.

After an explosion in a bio lab, the CSI team races to determine which nerve agent left one of their own unconscious, while the others explore a dangerous underground tunnel to find another CSI who got kidnapped during the blast.