A swindler and dobule-dealer, Rotondo served various masters. He was supposedly a professor of Latin and undoubtedly a fence of stolen jewelry. Rotondo was a regular visitor of the Palais-Royal, meeting with the Duke of Orléans there up to ten times a day to deliver intelligence.
Rotondo had an ongoing feud with the Marquis de Lafayette, whom he was accused of attempting to assassinate in 1790. Rotondo was also a regular visitor of nearly political club, keeping in close contact with the political leaders of the revolution. Rotondo was rumored to have been the murderer of Marie Antoinette's confidante, Princess Marie Louise of Savoy, during the September Massacres of 1792. Rotondo himself made no attempt do dispute this claim.
Frequently arrested for a variety of offenses, Rotondo went in and out of prison. Around 1795, he escaped the Grand Châtelet prison through the sewers of Paris, and presumably prepared to inform the Templar Order of his knowledge about the Assassins. The Assassin Arno Dorian was instructed by one his compatriots to infiltrate the sewers and kill Rotondo before he could reach the Templars. Reaching Rotondo before the National Guard, Arno was able to kill him.