In 1749, Latude invented a false conspiracy against Louis XV's mistress, Madame de Pompadour, secretly sending her a vial of poison followed by a letter warning her of the poison. Although Latude hoped to receive a monetary reward, Pompadour responded by having him imprisoned at the Château de Vincennes.
Latude escaped in 1750, only to be recaptured and incarcerated in the Bastille. In 1756, he escaped by climbing a chimney with a make-shift rope ladder fashioned from twine and firewood. Captured again, he was sent back to the Château de Vincennes, only to escape once more. Latude published his memoirs in 1787, in which he recounted his various escapes from prison.
As the French Revolution broke out, the Bastille was stormed and taken over by an angry crowd. Around this time, Latude contacted the Assassin Arno Dorian and asked him to recover the rope ladder from the Bastille, which was under heavy guard because of looting. After Arno returned him the ladder, Latude offered it with great pomp to the Hôtel de Ville. As the revolution progressed, he took every chance to present himself as a tormented victim of royal oppression. In one instance, he also escaped a well-wishing crowd that wanted to shake hands with him. Latude's famous ladder is exhibited at the Carnavalet Museum today.