In earlier episodes (Holiday Snaps (1983) and Come Out Fighting (1983)), Lee Montague's character is called Inspector Maurice Dupont. In this episode he is called Henri Dupont.
Near the start, as the still body is being dowsed in petrol, the eyes obviously blinking clearly show the victim to be alive and aware.
Inspector Dupont describes the wife of the missing man as "distrait" (French for distraught). However, since she is female, a French speaker would have automatically used the female version of the adjective, "distraite", which is pronounced clearly differently (the letter T near the end is pronounced in the latter case, but not in the former).