Raoul Duke is Hunter Thompson's alter ego. The alter ego often appears in Thompson's stories. Duke is a gonzo journalist who makes himself and his experience part of the story. Because of his heavy drug use and unconventional behavior, he fears exposure to authorities and subsequent arrest, but he also resents authority figures as well as those who might turn him in. This fear and resentment do not curb his behavior or drug use in any way, rather his behavior becomes an act of rebellion against the authorities who would rein him in. He thinks fondly of the freedom and hope inherent in the culture of the 1960s, particularly as that culture manifested in San Francisco, but that fondness makes him all the more disillusioned at the more conservative path American culture has taken in the early 1970s.
Dr. Gonzo is based on Hunter Thompson's friend, civil rights attorney Oscar Zeta Acosta. Dr. Gonzo functions mainly as an accelerant and enabler for Duke's activities in Las Vegas. He often advises Duke to engage in reckless acts, prefacing such advice with the phrase, "as your attorney." As his name implies, Dr. Gonzo is an agent of chaos in his own right. He often lashes out violently at Duke and at others who happen across his path, finding them threatening. He is sexually aggressive toward a waitress and creates a serious potential legal problem by giving drugs to a young woman and having sex with her under the influence, yet he is disgusted by some of Duke's more extreme suggestions.