This is the story of an obsession. Mona Lisa keeps smiling quizzically while our poor hero is pursued by her representation in all its forms, in all places. She smiles at him in a museum, at a bookseller along the banks of the Seine, in the streets, at a café. Enough to drive him up the wall!
| Actor | Role |
|---|---|
 Pascal MazzottiNarrator (voice) | Narrator (voice) |
 Cora VaucaireSelf | Self |
| LLéon CamyMagical painter (uncredited) | Magical painter (uncredited) |
 Boris VianMona Lisa smile teacher (uncredited) | Mona Lisa smile teacher (uncredited) |
 Anne Vernon(uncredited) | (uncredited) |
 Judith Magre(uncredited) | (uncredited) |
 Edmond TamizObsessed with the Mona Lisa (uncredited) | Obsessed with the Mona Lisa (uncredited) |
 Jacques Hilling(uncredited) | (uncredited) |