The evil Audrey Kensit
Audrey Kensit (Shirley Rumierk) is the main villainess from "From Russia With Drugs," episode 7.07 of Elementary(airdate July 4, 2019). She is the owner of Troy-Kensit Labs, and a friend of Cecil Troy.
Cecil Troy was one of two murder victims in the episode, the other being Ridley Dineen. It was quickly revealed that Cecil was killed by Ridley, leading Sherlock Holmes, Joan Watson, and detective Marcus Bell to Audrey, who spoke fondly of Cecil and mentioned their pasts as chemists. Though Audrey displayed a genial demeanor, it was a mask for her ambitious and greedy personality, as the episode's climax revealed that she was a villainous mastermind.
After Joan found a document that revealed everything, she, Sherlock, and Marcus confronted Audrey at her office, where the contents were uncovered. The document contained a bid from the lab to clean drug money that was laced with fentanyl, a bid that Audrey and Cecil won. However, after toxicologist dismissed the experiment as a fantasy, the DEA slowed down the bid, leading to Audrey and Cecil concocting a scheme to make the DEA force their hand. The plan involved Cecil luring Ridley to a safehouse, where Ridley stole an amount of money, all the while, Audrey and Cecil laced Ridley's inhaler. Ridley was killed, but not before he shot and killed Cecil.
Regarding the claims, the evil Audrey stated that they had evidence to things that Cecil had done, adding that she had no knowledge of his actions. However, Sherlock and Marcus revealed that hair from Audrey's cat was found in Ridley's room, and it was also uncovered that the villainess paid Pasha Voynov a six-figure sum to synthesize the drug that killed Ridley. Realizing that she had been caught, Audrey ended up arrested (off-screen) for her murderous scheme.