- Country: Belgium
- Genres: Adventure, Drama, Mystery
- Release: 1938-03-01
- Director: Léopold Simons
- Writers: Léopold Simons
- Language: None
- Stars: Edouard Bréville , Suzanne Christy , Line Dariel , Jean Darwels , André Duhamel , Guy Favières , Zizi Festerat , Hélène Ourgel , Pradelle , Paul Robert
- Runtime: 75 min
- Awards: N/A
- AKA: Le suicide de Zulma (France, French Republic) , Le mystère du 421 , Het geheim van 421 (Belgium) , The Secret of 421 (Belgium)
- Plot: Alphonse and his wife Zulma hold the 421, a tavern in the outskirts of Lille, in the North of France. It is always full of regulars who play cards there and drink gin and exchange words in ch'timi, the local patois. But there has been trouble lately: felonies have been committed in the surroundings. So who can be those two strangers who have just rented a room each at the 421? Each sets about doing a bit of detective work...
- IMDB:tt0256217
Le mystère du 421 Cast
Léopold Simons
Director
Edouard Bréville
Louis Bruxellois
Suzanne Christy
Elise Brassepeninck
Line Dariel
Zulma Brassepeninck
Jean Darwels
Le Sidi
André Duhamel
Johnny Brown
Guy Favières
Patron Commissaire
Zizi Festerat
L'agent
Hélène Ourgel
Sidonie
Pradelle
Désiré
Paul Robert
L'homme au foulard blanc