Wendy Vaughan (Amber Goldfarb) is the hidden main villainess from "Dark Triad," episode 3.08 of Ransom (airdate April 20, 2019). She is the VP of Risk Management at Hemmigan, a pharmaceutical company.
It was revealed early in the episode that Wendy is an ex-girlfriend of Oliver Yates, with the pair reminiscing while Cri-Res was investigating a string of poisoned insulin being distributed to diabetics, with 12 of them dying as a result. Eric Beaumont's negotiation revealed that the caller was Bruce Kaplansky, who demanded $50 million in exchange for releasing info on the poisoned batches, with Bruce revealing one of the batches that was tainted. After the payoff was made, Bruce was killed in an explosion, with Wendy expressing shock over the death and outrage over the lost money.
Oliver began to suspect that Wendy may have had a role in the tainted insulin, with Eric agreeing due to his statement that crimes like this are usually an inside job. Eric and Kate Barrett's interview with Wendy revealed a sociopathic side, with Oliver referring to her as a "dark triad," a person who possesses narcissism, ambition, and Machiavellian methods, in addition to a lack of empathy. Though the interview ended with Wendy expressing anger over the accusations and revealing that she knows about Eric and Kate's romantic relationship, Oliver is sent to record Wendy and incriminate her, with Oliver doing so with small talk at her house and reminiscing. During this point, Oliver reveals Wendy's ambitions persona as a reason for their breakup years ago, and he confronts her for using him to get ahead years ago.
Oliver also revealed that Wendy had to plead for the job she got at Hemmigan, but it was at that moment that he began feeling woozy and out of sorts, with Wendy revealing that she spiked his drink. As the group suspected, Wendy was looking to run Hemmigan, so she laced the insulin to kill patients to get her superior fired, after which she could prevent her own actions and be hailed as a hero. Bruce was a small-time conspirator in her plan, but when he became a weak link, the evil Wendy killed him by causing the explosion, using her Senator husband's car to drive to the cabin to commit the murder. Regarding Oliver, the villainess mocked his past relationship with Maxine Carlson, as well as blamed him for Maxine's role in a shooting years prior. Eric and Kate entered after they couldn't get a feed from Oliver's video, and rushed in the wine cellar after hearing a gunshot.
Oliver had shot Wendy, who claimed that Oliver was trying to kill her and was filing charges. During her hospitalization, Eric went to Wendy and made a negotiation: reveal the remaining tainted batches in exchange for her villainous actions being kept secret. Wendy does so, while defending her actions by stating that people like her are needed to do what's necessary, comparing herself to Alexander the Great and Genghis Khan. While Eric spoke with Cynthia Walker regarding the batches, Wendy gave an arrogant smirk, believing that she would get away with everything. However, police arrived and arrested Wendy for Bruce's murder, with the conceited villainess shouting at police and asking them if they knew who her husband was. Zara Hallam later showed video on Oliver's phone that revealed that Wendy grabbed Oliver's gun and shot herself, meaning that she was setting him up as an attempted murderer.