When Stella attends the Deputy Mayor Stewart Kaplan's charity gala with her firefighter escort, Brendon (from episode #503), the party is cut short after hundreds of balloons are unleashed from above, along with the body of their host. With the rank and file of the NYPD angered by the Mayor's decision, and Kaplan's support, of a temporary pay lag due to a budget crisis, many have a case of the "Blue Flu," calling in sick in protest and leaving the CSIs left to pickup the slack. The investigation leads to a variety of suspects including a bitter NYPD detective, a media mogul wanting to expose Kaplan's corrupt financial record, and Kaplan's thirteen year old son who is suffering from a form of OCD.