The newest member of the CSI team, Jo Danville, a former FBI agent, is welcomed to her new job by stumbling upon the body of a young woman murdered somewhere in the building that houses the NYPD Crime Lab.

When a young woman appears to be strangled while participating in a live online chat that Adam witnesses, the CSIs must determine if it was real or a hoax, and locate where the possible victim is.

When a married couple is found beaten in their home, a mother identifies her son as the killer and the CSIs believe they have their suspect, but all is not what it seems when another witness comes forward.

When the leader of a powerful New York gang, El Puño, is found murdered, the CSIs must find the killer before a street war with a rival gang breaks out. Mac asks the co-founder of El Puño, Luther Devarro, a man he put behind bars years before, for help.

A jewel heist at the penthouse of one of New York's most powerful attorneys takes a bizarre turn and the case leads the CSIs to a seemingly unrelated man in the morgue.

When a badly decomposed body found is an abandoned car on a rooftop, Mac and his team must go up against a killer who is using the parents of his victims to manipulate crime scenes.

Mac is on the hunt for a sniper who is using nitroglycerin in his bullets to explode on impact, and the prime suspect was once a missing boy from one of Mac's old cases.

As the CSIs investigate a case involving a woman who appears to have been scared to death in a supposedly haunted section of Central Park, Mac stumbles on another dead body buried nearby in the same part of the park.

When a woman's body washes up at the South Street Seaport, the CSIs unravel a dark secret from Deputy Chief Carver's past that threatens to shatter his stellar reputation and close-knit family.

Mac and the team search for the killer of a department store manager who was found dead in a holiday display window.

When a man in full clown costume shoots a bakery owner, the CSIs investigate and discover a decision from Flack's past that may put him in jeopardy.

When a Spanish club promoter is found dead, Mac must battle with the head of Barcelona's crime lab to solve the case.

When a tractor-trailer carrying exclusive party guests mysteriously ends up at the bottom of the Hudson River, the CSIs must solve the mystery from the soggy remains.

When the CSIs track down a suave and charming hitman, their investigation uncovers a conspiracy with far-reaching implications.

When a serial rapist is found murdered, restrained in the same manner as his victims, the CSIs weigh a feeling of justice against their sense of duty to pursue the killer.

When a conspiracy-obsessed woman is found dead, the CSIs investigate and discover that some of her theories may have had some truth to them.

When a popular student and star pupil at Manhattan's most elite private school is murdered, the CSIs find themselves immersed in the highly competitive world of over-privileged youth.

Jo balances personal and professional challenges when her adopted daughter, Ellie, is the key witness in a murder investigation.

While the team investigates the explosion of a gourmet food truck, Sheldon's new relationship could get him in big trouble at the lab.

The CSIs investigate a woman's death as the work of a serial killer, and Mac reconnects with his first partner after an ex-con they put away begins stalking him.

After a hail of gunfire tears through the crime lab, Mac and his ex-partner become part of a vendetta 17 years in the making.

Following a near-death experience, Mac becomes determined to close his last remaining unsolved case.

On the 10th anniversary of 9/11, Mac and the team remember specific moments from that day that were indelibly burned in their mind.

When an awkward teen is found dead, the team discovers that his efforts to win a sexy punk rock chick's heart may have gone a step too far.

When the body of a beautiful young woman is found in a stolen Ferrari, the investigation leads to a family of car thieves, but the CSIs must find the murderer before the rest of the family meets the same fate.

A night out for a friendly drink takes an unexpected turn when Danny and his rookie cops are caught up in a shooting.

The CSIs investigate when the recently paroled brother of a young basketball prodigy is implicated in a murder.

The CSIs investigate when a fraternity prank goes awry on Halloween and a pledge master is left for dead in an open grave.

When news of a high school house party goes viral, resulting in overcrowding, a collapsed porch and a teenage girl's death, the CSIs must use social media to uncover the truth about how she died. Meanwhile, Jo's final case at the FBI returns to haunt her.

As the CSIs investigate the assassination of a judge, Jo comes face-to-face with a criminal from her past.

When an important witness turns up dead, Jo is caught up in the dangerous investigation of the suspected rapist who was freed on her watch in D.C.

A charred body turns into a hot mess for the CSIs when it appears a cage fighter has been murdered by his stalker.

A home invasion investigation becomes more complicated when the victim's family turns out to be less perfect than they originally seem.

The CSIs investigate when a role-playing game turns lethal, with one player falling victim to a bona fide killer and the other kidnapped and held for ransom.

When the CSIs investigate two seemingly unrelated deaths, their separate trails of evidence lead to a surprisingly connected conclusion.

When a lab tech is murdered in a case that has eerie similarities to a 1950's cold case, the CSIs get a glimpse into what goes on in the shadows of the lab.

The CSIs find themselves immersed in the world of competitive video gaming when they discover a murder may be related to a high-stakes tournament.

A wave of brutality threatens a small New York City community when a body is found dismembered and strategically left out on four street corners.

The CSIs are called to a Brooklyn housing project to investigate the murder of a successful businessman who still felt the pull of his old neighborhood.

When Mac is shot, he finds himself in limbo between life and death and, as he fights for his life, it's up to his team to bring the shooter to justice.

The CSIs investigate when a fire chief - a friend of Mac's - is killed in a blaze that used the same technique as a recently paroled arsonist.

Il team è in lotta contro il tempo per fermare un piromane di nome Leonard Brooks che sta usando il fuoco per vendicarsi di persone del suo passato.

La squadra si reca a San Francisco alla ricerca di una sedicenne che potrebbe essere stata uccisa. Jo ha problemi ad affrontare il caso che la colpisce nel privato.

The CSIs race to catch a shooter when Lindsay is injured during the attempted murder of a political candidate, and the events in the aftermath lead to a child's death.

La squadra si sta occupando di un caso vecchio di vent'anni riguardante la scomparsa di un bambino poiché l'uomo sospettato all'epoca di aver commesso il crimine viene ritrovato assassinato. Non c'erano prove sufficienti per un'accusa nel passato, ma l'omicidio potrebbe essere una vendetta postuma da parte della famiglia.

The CSIs investigate a twisted fairy tale when a woman in a ball gown is found at the bottom of the pond outside Belvedere Castle in Central Park.

Il team sta indagando su una serie di omicidi e durante la raccolta degli indizi si scopre che il killer sta mettendo in scena le scene di un famoso gioco da tavolo.

The CSIs must delve into the high-pressure world of an elite prep schools when a student is murdered while studying for the SAT'S. Meanwhile, Lindsay returns home to Montana to visit her father and deal with some issues from her past.

Il passato del detective Lovato come agente sotto copertura viene nuovamente a galla quando uno dei membri della gang dove si era introdotta viene ritrovato brutalmente ucciso.

The CSIs investigate a 1920s-inspired speakeasy when one of its owners is murdered and $10,000 goes missing. Meanwhile, Adam spends his day off in an unexpected way.

Due uomini sono ritrovati morti ma l'unico dettaglio in comune è il metodo poco convenzionale con il quale sono stati uccisi. Intanto la squadra deve vedersela anche con una serie di assegni anonimi di cifre esorbitanti che stanno fioccando in tutta la città.

Jo e Lindsay sono alle prese con un caso difficile che riguarda l'uccisione di un agente. Durante le indagini devono fare i conti con l'enorme impatto emotivo subito dalla famiglia della vittima e allo stesso tempo devono mettere da parte i loro sentimenti personali per riuscire a chiudere il caso.

Il team indaga sulla morte di un uomo mascherato trovato ai piedi di un grattacielo, noto per essere teatro di una serie di morti misteriose.

Un pizzaiolo viene aggredito e la sua auto dirottata e il team deve scoprire qual'è il vero scopo degli aggressori.

Mac e il suo team fanno squadra con Russell per riuscire ad avere la meglio sui rapitori di Christine prima che sia troppo tardi.

La squadra si occupa di tre omicidi collegati ad altrettante storie d'amore. La condizione medica di Sid sta causando dei problemi sul lavoro, mentre si scopre che il Danny e Lindsay stanno aspettando un maschietto.

La polizia è accusata di aver ucciso un uomo disarmato e il dipartimento viene invaso da un gruppo di protestanti. Mac e Flack rimangono coinvolti nel caos della situazione mentre il resto del team cerca di risolvere il caso.