I just finished watched Versailles Season 3, Episode 4 "Crime and Punishment" on Netflix.
At around 37 minutes 50 seconds, a lady goes to get a bottle from a secret place where a man hands her the bottle. She gives him some money in a bag in return. Then, around 46/50 minutes in, the same lady that had the bottle, sneaks to the king and queen's master bedroom, over to the pillow, and sprays it out underneath it.
Later on, if you go to 51 minutes and 20 seconds, you see that when the queen goes to sleep, an ant is crawling from the pillow to the queen's ear.
She gets sick, and later she dies.
My question is: what did the lady get from the man, and what kind of ant is it that got her sick and caused her death?