On 5 May 1789, Lafrenière sent Perrault to deliver a letter to Templar Grand Master François de la Serre in person. The letter warned the Grand Master of a plot within the Templar Order to kill him and put François-Thomas Germain in charge.
Perrault reached de la Serre's estate just as the Grand Master left for the Estates-General in his carriage. De la Serre's adopted son Arno Dorian agreed to deliver the letter to him personally. However, Arno was forced to flee the Estates-General after a fight and later left the letter in de la Serre's office, being preoccupied with courting his love interest, Élise de la Serre.