- Country: France
- Genres: Comedy
- Release: 1967-11-29
- Director: Jacques Besnard
- Writers: Jacques Besnard , René Cambon , Jean Halain
- Language: French
- Stars: Jean Lefebvre , Maria Latour , Bernard Blier , Pierre Brasseur (1905–1972) , Michel Serrault , Robert Dalban , Mario David , Margo Lion , Henri Virlojeux , André Chaumeau
- Runtime: 90 min
- Awards: N/A
- AKA: Le fou du labo IV , Il morto mettetelo sul conto (Italy) , The Madman of Lab Four , A 4-es labor őrültje (Hungary) , Szaleniec z czwartego laboratorium (Poland) , Um Ingénuo Diabólico (Portugal, Portuguese Republic) , Der Verrückte aus Labor 4 , A négyes labor őrültje (Hungary) , Der Verrückte von Labor 4 , Le Fou du labo 4 (France, French Republic)
- Plot: Eugène Ballanchon, a young talented researcher, is constantly persecuted by his rascal parents, with whom he lives, but also in the laboratory, by his boss, whose anger terrorizes him. One day, while testing a truth serum, he made an error in handling and developed a particularly effective laughing gas. He successfully experiments it on his boss. This discovery attracts the attention of Beauchard, the director's secretary, who engages in industrial espionage on behalf of a foreign power. Beauchard instructs the pretty Régine to seduce the innocent Eugène, while the DST sends two inspectors to protect the brilliant inventor from a process which could, we hope in high places, prevent war forever.
- IMDB:tt0131401
Le fou du labo IV Cast · · · ALL
Jacques Besnard
Director
Jean Lefebvre
Eugène Ballanchon, chercheur scientifique, célibataire
Bernard Blier
M. Beauchard, secrétaire de direction lié à un gang
Michel Serrault
M. Granger, directeur du laboratoire scientifique
Pierre Tornade
l'inspecteur DST
Pierre Brasseur
(1905–1972)
le Père Ballanchon
Margo Lion
la Mère Ballanchon
Robert Dalban
Marchand, un espion dans le laboratoire
Mario David
Mario
Paul Préboist
L'agent
Henri Virlojeux
un savant
André Chaumeau
Le baron
Jean Franval
Un inspecteur de la DST
Alain Janey
Fred
Sabine Sun
La baronne
Yvon Sarray
Le piéton
André Cagnard
Jo (uncredited)
Guy Delorme
Un acteur du western (uncredited)
Marius Gaidon
Un agent de police (uncredited)
Henri Guégan
Un acteur du western (uncredited)
Jean Ozenne
Le ministre (uncredited)
Laure Paillette
La voyageuse (uncredited)
Lionel Vitrant
Un acteur du western (uncredited)