After completing the game you can enter The Louvre and play "The Louvre Revisted" bonus level. The puzzles are on the paintings that represent each of the nine levels of the game.

The Louvre Museum Painting: "YOU SHOULD NOT HAVE RUN MONSIEUR SAUNIERE NOW TELL ME WHERE IT IS"
St. Sulpice Painting: "THE SISTER MUST HAVE BEEN CALLING PRIORY MEMBERS WHEN SHE WAS ATTACKED"
Normandy Mansion Painting: "ITS THE PRINCESS SOPHIE KEY MY GRANDFATHER PROMISED ME"
Bank of Zurich Painting: "IT IS THE CRYPTEX THIS IS BASED OFF OF A DESIGN BY DA VINCI"
Chateau Villett Painting: "THE LEGEND OF THE HOLY GRAIL IS A LEGEND ABOUT ROYAL BLOOD"
Biggin Hill Airfield Painting: "SAUNIERE BROUGHT US TOGETHER TO FOLLOW THESE CLUES FOR A REASON"
Temple Church Painting: "SILAS TAKE THE KEYSTONE FROM MR LANGDON TEABING IS OUR HOSTAGE NOW"
Westminster Abbey Painting: "TEABING FELT THE TRUTH CRASHING DOWN ON HIM THE GRAIL WAS LOST TO HIM"
Rosslyn Chapel Painting: "THE QUEST FOR THE GRAIL IS THE QUEST FOR THE DIVINE IN EACH OF US"