After a six-year-old boy dies in a school shooting, detectives trace the gun used back to a white supremacist's gun shop. Munch and Tutuola both face hatred and prejudice from the major suspects in the case, but their investigation soon takes them from the man who pulled the trigger back to the gun shop owner, who makes no bones about his hatred of anyone who isn't white.

Undercover FBI agent Dana Lewis returns to help the detectives with a case.