There'sno source mentioned, but according to this (French TV station's) presentation (see slide 5)[0], Commissaire Fichet from Les Diaboliques was indeed an ins

There'sno source mentioned, but according to this (French TV station's) presentation (see slide 5)[0], Commissaire Fichet from Les Diaboliques was indeed an inspiration. [0] https://tvbreizh.fr/sites/default/files/dossier_de_presse_50_ans_de_columbo_novembre_2018.pdf https://tvbreizh.fr/sites/default/files/dossier_de_presse_50...