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