Revealing mistake: The Simon brothers manage to make their escape and Magnum and TC get back to Robin's nest reaching Rick and Higgins. From the open door you can see a single real plant, and a matte painting to act as background. (00:34:15)
Did You See the Sun Rise? - S3-E1
Revealing mistake: Going through the database with Lieutenant Maggie Poole, Magnum spots finally Ivan's picture. This involuntary puts a rather hilarious twist to one of the most famous and dramatic endings of a TV episode, since that picture from the military intelligence database is exactly from the 'future', aka the ending of the episode; Ivan is wearing the same black suit and tie (pretty weird already with the setting) that he will wear in the ending, and is even in front of the same tree leaf by leaf. (01:13:30 - 01:34:20)
Foiled Again - S3-E7
Other mistake: The culprit does not have wounds on their hands, but whoever tampered with the box left blood inside it. If the blood is irrelevant to the case and could have been left by Higgins, then it's unclear why it has an effect on the culprit and make them admit their guilt.
Foiled Again - S3-E7
Continuity mistake: When the contestants are announced (in a thick French accent), it is said that Higgins fences from the right position. Rick later states, accusing Higgins, that "A lot of people heard Higgins ask for the right side." When the odious rival shows up, he says "You asked for the left position?" to which Higgins nods. (00:11:50 - 00:13:00)
Foiled Again - S3-E7
Other mistake: At the beginning of the episode Magnum has some banter with Higgins, but also needs his help with a tie knot he's clueless about, to the point that he can't even pronounce its name and calls it "double Winslow", with Higgins promptly correcting him. And he's completely useless at doing it. However, in the previous season's episode "The Last Page", Magnum was helping Rick with his tie and giving him expert and sensible advice about it and explicitly referencing the Windsor knot, in fact discussing the merits of the half Windsor.
Foiled Again - S3-E7
Continuity mistake: When Magnum confronts the real culprit, in the couple of POV shots they are not wearing the gloves they have in the rest of the fight. (00:43:40)
Foiled Again - S3-E7
Continuity mistake: After hearing from Magnum about Velma Troubshaw's conversation with the DA, Higgins shows up at her mansion and knocks at the door. The shadows of the foliage (and the shadow of John Hillerman himself) change noticeably at the cut. (00:37:00)
Foiled Again - S3-E7
Continuity mistake: Magnum visits Assistant District Attorney Carol Baldwin who is having her lunch break outside. She has a paper towel around the yogurt container she's eating from, but when the camera is to her left the napkin reaches the rim of the container, whenever the camera is to her right it's an inch lower. (00:21:45)
Foiled Again - S3-E7
Continuity mistake: Higgins is dressing up for the foil duel. He puts his right glove on when Velma apologizes, and when he replies that she has nothing to apologize for...he's putting the glove on again. (00:12:25)
Foiled Again - S3-E7
Continuity mistake: Before the fencing match, Higgins' old belle Velma Troubshaw approaches him and they chat. During this chat the people behind Higgins are different from shot to shot, matching only the views from the same angle. (00:12:20)
Foiled Again - S3-E7
Continuity mistake: Higgins is staring at the window after his dream. Magnum calls for him and casually walks into the study. Something changed in this second part of the scene; the black cap that will be a conversation point later is now placed across the lid and main case of the foil. In the opening view, it was entirely on the lid and wasn't on the frame. (00:03:05)
Revealing mistake: In present day, Magnum is flying with TC to the old house. Selleck and Roger Mosley are talking inside the vehicle about being there before, and TC's shirt is dark red. However in the wide shot of the landing, whoever is piloting the chopper is wearing a yellow shirt. (00:43:40)
Continuity mistake: At the end of the episode, Thomas is sitting by Higgins that is playing Pac Man. TC arrives and Magnum stands up. There are two towels on the wall, and they are one on top of the other not overlapping by about 3 inches. By the time TC is in the water with Magnum, they are stacked perfectly. (00:46:30)
Continuity mistake: Rick gets KTFO by the mace being thrown at him. He collapses unconscious on the carpet that makes a noticeable hump, and his arm is past the pillar. Magnum comes to his rescue, and Rick is still out but the carpet straightened itself and Rick's arm is by his body. (00:32:30)
Continuity mistake: Higgins is still awake and Magnum sits on the couch with a glass of milk and a cookie. Between shots, the glass fills up - initially it was at the level of his middle finger, afterwards it moved up above his index. (00:29:20)
Visible crew/equipment: After the chat on the intercom with Rick, Higgins storms back to the phone. Meanwhile Magnum approaches the window. On the wall on the left of the frame, the shadow of the boom mike appears. (00:18:30)
Audio problem: Higgins watches Magnum spit what he chewed on and gives him a "Magnum..." full of contempt. Magnum responds ever cheerful "Sorry, want a bite?" but the audio of the sentence is much lower than in the rest of the scene. (00:13:10)
Continuity mistake: Higgins is interrupted in his reading of Lord Byron's "So, we'll go no more a roving" by distinctly un-African music. As it happens, the book in his lap changes angle entirely in his lap. (00:06:15)
