Other mistake: Twice in the episode it is explicitly said that Magnum's phone has been disconnected, and that Higgins checked with the phone company. Yet at the end, it turns out 'the lads' chewed on the cable. Surely the phone company wouldn't tell the estate manager that the line has been disconnected for billing problems (so, a well determined administrative issue with proper paperwork done) when it's a wiring problem.
Continuity mistake: Magnum is going to deliver the blackmail money. As he gets out of the car in the aerial longshot, he has dark shoes, as opposed to the white trainers he sports during the episode. (00:13:20)
Revealing mistake: After Magnum gets punched by Ted Danson, he drives off. Oddly enough, he drives by TC's van, parked in front of one of the villas of the area, and that has no business being there. (00:24:05)
Continuity mistake: In the climax of the episode, Magnum forces Amy to look away using the left hand, then the right hand. (00:42:00)
Continuity mistake: When Rick tosses the disgusting burger mess on the table inviting Higgins to "have some lunch", in the reaction shot on John Hillerman someone from out of frame puts down a bottle of Coops that is quite literally full to the brim. Next we see Rick laughing, but his bottle is half empty. (00:27:15)
Continuity mistake: When TC says "This ain't no lunch", his right hand jumps on the table, when it was off it when he dropped the burger in its box. (00:25:15)
Continuity mistake: Inside Frank La Rue's apartment, Magnum approaches his suitcase. The position of the suitcase in the POV shot does not match at all the following view. (00:19:40)
Other mistake: Magnum runs away to chase the sniper. A few extras promptly start yelling and screaming despite the fact that from their position they can't have properly seen the victim of the sniper yet (and there's no blood). (00:14:50)
Visible crew/equipment: Magnum lost the car he was chasing. He comes across a police car and stops at the crossroads to avoid getting stuck giving too many explanations. The road is outside of town and kinda in the middle of nowhere, but in the side mirror there's a bunch of people watching the scene. (00:16:20)
Continuity mistake: Mrs. Kimball's wheelchair and Mrs. Kimball herself are in position and angles different in each shot during the scene of the fall; the chair faces right, left, right, and the old lady is suddenly perfectly on the ramp at the end after falling prone. (00:05:40)
Revealing mistake: Mrs. Kimball falls off the wheelchair in an alternative take, featuring a stuntperson instead of the elder actress. Problem is, the stuntperson is barefoot, and Mercedes McCambridge wears socks and slippers. (00:05:50)
Revealing mistake: When Agatha Kimball gets her wheelchair caught in a gap between the step and the ramp, stagehands can be seen as they safely hold Mercedes McCambridge to avoid her getting hurt. (00:05:45)
Continuity mistake: When Agatha Kimball tells Amy at the piano "No, I was talking about your cologne", Andrea Marcovicci's hands both jump on the cup at the cut. She was holding it with just one hand. (00:05:00)
