The eyes, Chico, they never lie" is that a person's eyes reveal their true emotions and intentions, even when their words or actions are deceptive. This iconic line from the movie Scarface suggests that the eyes are a window to the truth, betraying feelings like fear, guilt, or pain that a person may be trying to conceal. It's a concept rooted in nonverbal communication, highlighting how body language can convey honesty and hidden feelings that words cannot.