- Augustin: "Here for a fight, monsieur?"
- Arno: "Come again?"
- Augustin: "A training match, that is. An Assassin can never be too well-prepared."
- Arno: "Isn't our mandate to work in the shadows? Stay undetected and all that?"
- Augustin: "Call this the fallback option. Better to practice here in safety than pick a fight with ruffians in the streets, no?"
- —Augustin Grisier meeting Arno Dorian.[src]
Augustin Grisier was a French Assassin of African heritage and the fencing master in the Café Théâtre owned by Arno Dorian. Augustin frequently trained with Arno in and out of the Café, honing his fellow Assassin's skills and fencing prowess with various weapons.
In 1793, Célestine, the servant girl of the Café Théâtre saw Augustin and Charlotte Gouze whispering together at midnight about the imminent closure of the convents of Paris, a dechristianization of the Revolutionary France which was greatly upsetting for Augustin. The young girl gossiped it to the intendant, who subtly told her to mind her own business by asking her what she was doing out of her room at midnight.
Later, bottles from the wine cellar of the café were stolen and the cook lady reported it to the intendant, telling him that she had seen Mr. Colignon, the gardener recommended by Augustin near the cellar. The intendant spoke of the matter with Célestine who did not believe in the guilt of Colignon, saying that as a gardener he didn't have the key of the cellar. Still suspicious, the intendant asked Célestine to follow Grisier and see what he was doing outside of the Café, because he found him mysterious and did not like to know so little about someone living in his house.
- Grisier is probably related or is loosely based on a famous fencing master of the same name born in 1791, Augustin-Edme-François Grisier, who was also known to be a good friend of the writer Alexandre Dumas, the son of Thomas-Alexandre Dumas.