Continuity mistake: During the informal interview with the singing neighbour, the position of her hand with the brush changes between cuts, and when the inspector tries to bluff saying he has business with the suspect, she has an empty hand, but after the cut she is holding the powder box. (00:38:05)
Revealing mistake: Lomenzo and his partner pay a visit to the neighbour of the suspect. She is powdering her face, or so it should be; you can tell the brush has no blush, and the powder box is empty (you can see almost the entirety of it when she tips it during her chat, and it's squeaky clean inside). (00:38:20)
Visible crew/equipment: When Lomenzo meets the real killer (or is it?) at the estate, you can tell which angles were shot by a certain camera, because there's some dirt/grass filament on the lower part of the lens that keeps popping in frame whenever it cuts to certain angles - such as the frontal shots with the man holding the rifle, or the close-up inside the cage. (01:10:00 - 01:12:00)
Continuity mistake: In the flashback showing her possible true death, Rosa starts drinking from a glass that is almost full, but not quite. At the first cut, the glass refills itself and she is holding it closer to the base. (01:08:20)
Continuity mistake: Eli Wallach dismisses the ex cop and the ex hitman and taps on the table to call attention from his clients. Cut, and he's suddenly holding the walking cane by the handle, instead than mid-length. (00:59:45)
Continuity mistake: Corinne Clery is kissing the inspector, straddling his lap while they discuss exotic locations and feral contraband. She has his hands behind his neck, fastened, but at the cut they are apart and only then she brings them together again. (00:57:10)
Revealing mistake: At the pork processing plant, a close-up from an Italian newspaper "Corriere della sera" shows news from November 18, when it's established from previous conversations that the killer was captured on November 30th, so it should be a December newspaper. (00:53:00)
Audio problem: In the car scene with the police transporting the prisoner from the cemetery to the station - before he makes an adventurous escape - the protagonist is barely visible through the very pronounced reflection on the windshield; however, when you can see his face, his lines appear to be completely dubbed over and don't match the lip movements at all. (00:49:10)
Other mistake: When the former pimp brings fresh flowers for Rosa's tomb, the gravestone says she died in 1972, but both the inspector and his colleague said on separate occasions that the murder happened 4 years before - and the movie is set in 1975 and at the exact same day of her death. (00:48:30)
Continuity mistake: After making love with Corinne Clery, the protagonist asks her when did the prostitute at the party die. The date mentioned is November the 30th, and he says "It's today", but the politician's obituary was dated November 18th. (00:48:00)
Revealing mistake: In the close-up of the supposed killer updating his album with the obituary of the politician murdered on air, amongst the listed surviving family members of the male politician there's also a husband. Not quite likely. (00:28:50)
Continuity mistake: Eli Walach pushes with his cane the cigarette packet closer to the Inspector; in close-up the packet starts off much further from Lomenzo than its original position. (00:17:25)
Revealing mistake: When the mistress is burnt alive, she does not seem all that bothered, and simply pulls at ropes blatantly too loose to hold her, which constrain her just at her neck - in fact she pulls at them so weakly probably to avoid ruining the prop. It should also be noted that it's a normal rope, and yet it's perfectly intact after the fire that devastated her face and coat. (00:16:50)
Revealing mistake: When the prostitute is grabbed by the villain, he stuns her with a smack on the top of the head, since the strangling did not seem to work all that well. Thing is, she goes limp only a second after the sonic boom of a sound effect. She also somehow stays perfectly straight against a tree; she sleeps on her feet like a horse, evidently. (00:15:35)
Revealing mistake: Lomenzo needs to search through the police archive, and his coworker guides him through it. He opens a drawer where there are 3 folders containing case files starting with the letter A (including a ludicrously generic "Associates"). When he opened it, the labels on the front of the drawers were all starting with letter V. (00:10:35)
Continuity mistake: Inspector Gaspare Lomenzo arrives home and bickers with his girlfriend. After telling her that he's her "white slave", he leans against the counter; his hand is on the corner in the wider angle, on the front in the close-up. (00:09:20)
Revealing mistake: The protagonist figured out that the killer is following the "Shaggy Peter" nursery rhyme and explains it to his colleague. A close-up of the supposed killer follows, putting together an album with obituaries. The obituary to the left is an obvious fake; its bottom half begins with half a word mid-sentence, and it mentions a daughter-in-law; the actress Greta Vayan playing the victim - a prostitute - was in her early 30s. (00:07:50)
Audio problem: When the commissioner gets to the station at the beginning of the movie, a trans greets him, but their mouth does not move when they talk. (00:04:30)
Revealing mistake: In the second murder, the killer of the first one is bashed in the head by a monkey wrench, her head split open. A second hit ensues, but there's no reaction to it, no further spraying or damage, the head itself barely moves, and with delay. (00:04:30)
Character mistake: The first victim gets smacked in the face by the Mistress, and then in subservient fashion holds her hand and kisses it asking if she hurt her hand hitting him. Thing is, she slapped him with the right hand and he is kissing the left better. (00:01:40)