Jealous that the waitress is beating her to the altar, Dee does everything in her power to derail the wedding. Meanwhile, the guys distract Charlie by getting him back in the dating scene.
The gang attends their high school reunion with a lot to prove. Old friends are met and new foes are made as the gang trips down memory lane.
In the conclusion of this two part episode the gang devises a new plan at their high school reunion to make sure their tarnished high school images will now sparkle and shine.
When a mutilated sex offender is found dead, it is unclear if he was the victim of a hate crime, sexual assault or self mutilation. As Intelligence questions those related to the case, they find themselves up against a private "special police" force who may be covering up illegal activities. Meanwhile, Halstead (Jesse Lee Soffer) runs Jimmy's (guest star Tony Crane) DNA to confirm that he is actually Lindsay's (Sophia Bush) father.
When a charred body is found in a torched house, Intelligence must work to identify the victim, as well as a young boy who is found badly injured inside. As they look to determine the cause and who may have been involved, they are faced with a web of secrets and lies. Meanwhile, Lindsay (Sophia Bush) and Halstead (Jesse Lee Soffer) receive an odd warning about Rixton (guest star Nick Wechsler) that leaves them suspicious.
