In 1677, Montespan made it clear that if the King should abandon her, she would have him killed. When the King entered into a relationship with Angélique de Fontanges in 1679, Montespan called for La Voisin and asked her to have both the King and Fontanges killed. La Voisin hesitated, but was eventually convinced to agree. At the house of her colleague, Catherine Trianon, La Voisin constructed a plan to kill the King together with the poisoners Trianon, Bertrand and Romani, the last being the fiancé of her daughter. Trianon was unwilling to participate and tried to make her change her mind by constructing an ill-fated fortune for her, but Voisin refused to change her mind. The group decided to murder the King by poisoning a petition, to be delivered to his own hands.