Episode 412, "Knuckle Up" Tomorrow 12|11c
SEASON 7, EPISODE 721A - In part one of this two-part episode, the team investigates the 1989 case of a prom queen who was killed after her prom by a potentially deliberate hit-and-run driver. Meanwhile, Rush tries to ignore her father's appeals to give her troublemaker sister, Christina (recurring guest star Nicki Aycox -- Dark Blue), another chance after she suddenly resurfaces. Recurring guest star Raymond J. Barry appears as Paul Cooper. Guest star Kerry O'malley (Brotherhood) appears as Suzie Hill, the prom queen's closest friend in present day.