Marta Cabrera

Marta is Harlan's nurse and has his trust. On the night of the party, she thinks she mixed up his medicines and that he is dying. Harlan gives her instructions to leave, sneak back in and keep an alibi. After his death, she can't lie to the detective without vomiting, so she gives answers that are true but incomplete. At the reading of the will she learns Harlan left her everything, and the Thrombeys try to pressure her by threatening her mother's deportation.

Marta runs off with Ransom, who manipulates her into confessing. She gets a blackmail note and learns that Fran, the housekeeper, sent it. She finds Fran drugged and performs CPR. In the end, Blanc shows she didn't kill Harlan: Marta gave the right medicine, which she recognized by its feel. Ransom had swapped the medicines. Marta pretends Fran is alive, and Ransom confesses to the crime. She ends on the balcony of the mansion, now hers, sipping coffee from Harlan's mug.

Marta can't lie: when she tries, she vomits. So Harlan's plan gives her a way to tell only the truth, even if incomplete. With the police and with Blanc, she answers exactly what is asked, without frills, and hides evidence that incriminates her.

After the will, grandson Ransom helps Marta run and gets her to confess to him what she did. In exchange for help, he asks for a share of the inheritance. The other Thrombeys try to talk her out of the money and threaten to deport her undocumented mother. Marta knows that if she tells the Thrombeys the truth, she forfeits the inheritance under the slayer rule.

Marta Cabrera was created for Knives Out (2019). Ana de Armas plays her, and the film was one of the year's box-office hits, with $311 million. She doesn't return in the following films, which have new casts.