Here is the full list of all 27 Thieves Gambit: The Curse of the Black Cat achievements.
Escape the palace.
Become the world's most famous jewel thief.
Steal the Black Cat.
Revealed Ludomir Ivankov.
Went in through the front door.
Start a romance with Rania.
Investigate the palace.
Dance with Rania.
Charmed the Duchess.
Recruited Nick.
Escape the city.
Recruit Nora.
Recruit Rania.
Escape the Paris police.
Recruit Le Roux.
Charmed the Duke.
Charmed the heir.
Dance with Nick.
Discover Nick's true identity.
Start a romance with Nick.
Started a romance with Bouchard.
Went in over the garden wall.
Went in disguised as a maintenance team.
Refused to join Bouchard.
Teamed up with Bouchard.
Double crossed Bouchard.
Succumb to the Curse of the Black Cat.