Marcel Denis made his comics debut aged 17 in 1940 in Le Petit Vingtième with the scout story Pip.

[2] Salvérius, the future artist for Les Tuniques bleues with Raoul Cauvin, had been hired by Dupuis thanks to Marcel Denis.

[9] In 1959, Marcel Denis returned to the atelier of Franquin to collaborate on a collective story, L'Île au Boumptéryx,[A 2] created for a special Easter issue of Spirou magazine.

[10] In 1958, when Denis had left the Franquin atelier, he created Les Frères Clips, a series of gag pages and short stories, his first comics for Spirou magazine.

It told the story of two inventors, Jules and Jonas, whose well-intended ideas often result in catastrophes when presented to their boss, minister Beaussillon.

[13] In 1960, Maurice Rosy, writer of Tif et Tondu and artistic director of Spirou, suggested that Denis should take over the illustrating of the strip.

[14] Denis made two episodes of the series, Tif et Tondu à Hollywood in 1960 and Ne tirez pas sur Hippocampe!

[13] Denis' Tif et Tondu à Hollywood was finally published as an album in 1983, and Ne tirez pas sur Hippocampe!

Hultrasson is a Viking beer salesman whose main other activity is to prevent the stupid Sépadeffasson taking the throne of king Harald-les-beaux-cheveux.

[16][A 4] Marcel Denis wrote the first three long stories published in ‘’Spirou’’: Fais moi peur Viking!

[14] After a second and final row with Marcel Remacle and serious health problems,[14] Denis left the comics field in 1971 to get a more steady job with a printer.