L'assassin habite au… 21
- Jier: 1942
- Lân: France
- Sjenre: Comedy, Mystery, Thriller
- Studio: Continental Films
- Keyword: paris, france, based on novel or book, serial killer, boarding house, french noir, police inspector
- Direkteur: Henri-Georges Clouzot
- Cast: Pierre Fresnay, Suzy Delair, Jean Tissier, Pierre Larquey, Noël Roquevert, René Génin