Voight calls the team to investigate a homicide involving the only witness in a rape and murder case against an extremely young man, Oliver Tuxhorn. Intelligence looks into Tuxhorn's family and their finances as they try to determine if someone was paid to take out the victim. Meanwhile, Stone offers Antonio a job as lead investigator for the state attorney's office, and Burgess and Sorensen's body cameras capture a bizarre exchange with a man that they pull over.