The New York CSI department welcomes a new member to the team in season 7, former FBI agent Jo Danville is immediately in the line of fire when she stumbles over the body of a young woman who has been murdered within the NYPD crime lab. Detective Mac Taylor meets a desperate family in search of their missing son but has problems of his own as a hail of gunfire rips through the crime lab. Along with his ex-partner Mac becomes part of a vendetta some 17 years in the making.