This pair of exquisitely allusive portraits shows the Argentine master reckoning with denial and failure. Martel’s psychological study in culpability, The Headless Woman, plumbs the depths of human nature, as well as questions of class, race, and Argentine identity. In her hugely acclaimed follow-up, Zama, a Spanish royal functionary flounders in 18th-century South America, where the iniquities and absurdities of colonialism are on parade.