Criminal Minds Episode 8.09 Magnificent Light

The BAU tracks an UnSub with a bizarre case of synesthesia - not only does he physically see words that are spoken to him, but they change colors depending on the mood of whoever is speaking them. Believing that red-colored words are only spoken by truly evil people, the UnSub decides that he must use his gift and kill those who he alone knows deserve it. After his first few kills, the UnSub decides to enlist a partner - famed motivational speaker Barry Flynn. Flynn's speeches gave the UnSub his motivation and drive to act, so the killer decides to kidnap his hero and force him to participate in his murder spree.