Continuity mistake: When Magnum and Rick find TC's office wrecked, Rick picks up a brochure and holds it out to Magnum in his right hand, with the team ring on his finger, but in the next closeup the ring has vanished. (00:41:50)
Visible crew/equipment: When Magnum gets the bank vault door open he rushes to get Susan, and the boom mic moves around at the top, center of the screen. (00:38:05)
Visible crew/equipment: While Susan and Magnum are locked in the vault, when Susan pours the last of the wine into Magnum's cup and in following shots, the shadow of the moving boom mic is visible behind Magnum. (00:33:15)
Visible crew/equipment: While TC is driving the van helping Benny deliver the newspapers, the hidden mic taped to Benny's chest, under his shirt, can be seen in a few shots from the van's passenger window, during this scene. (00:32:30)
Visible crew/equipment: When Magnum walks into the guesthouse and finds Danny inside drinking one of his beers, the white tape marks are visible on the middle couch cushion, where Magnum will be sitting in following shots. (00:13:10)
Operation: Silent Night - S4-E10
Visible crew/equipment: While Higgins, TC, and Rick are on the beach, Magnum is wearing the Santa suit as he runs over to them singing and carrying a quirky little tree, and in the shot facing all four men, lighting equipment is visible at the right side of the screen. (00:39:25)
Operation: Silent Night - S4-E10
Visible crew/equipment: When TC first starts singing "Under the Boardwalk" while he's fixing the chopper, just as he leans over the toolbox, the legs of a crew member wearing jeans are visible under the chopper, at the left side of the screen. It cannot be Rick, who's wearing white slacks, or Higgins, who's wearing his typical trousers, or Magnum, who's in shorts since he removed the Santa suit. (00:15:55)
Operation: Silent Night - S4-E10
Visible crew/equipment: When TC makes a successful crash landing on Frenchman's Island everyone exits the chopper, and as Rick says, "Hey, you know what this place is," the boom microphone is visible moving around at the bottom left of the screen. (00:05:30)
Visible crew/equipment: When TC pulls the van up to the estate gate, he and Leon walk over to the gate, and the white tape mark is visible on the ground in front of the gate. (00:05:35)
Squeeze Play - S4-E7
Visible crew/equipment: While Buzz and his "exhibitionistic entourage" are at the estate, when he tells Higgins that he wants to make Robin's Nest fun, the reflection of the reflector screen is visible on the lenses of his glasses. (00:12:30)
Visible crew/equipment: After TC crashes into the pigpen fence he offers to take Leon to the hospital, and just as TC lifts Ima and places her inside the Ferrari, the tip of the low boom microphone is visible as it moves, at the left side of the screen. (00:05:10)
Squeeze Play - S4-E7
Visible crew/equipment: During softball practice and the practice with Killer, there are moments where there are visible rectangular outlines of the hidden mic transmitter on a player's back. Two examples are, when Magnum is up at bat Rick bends over to pick up a ball and the bulge is on Rick's back, and when Lola slams her bag of tip money into Killer and she bends over him the bulge is on Lola's back. (00:10:05)
Visible crew/equipment: At the bingo fundraising event, in the shot from behind TC as he hands someone a few bingo cards, as the camera moves backward two white tape marks are visible on the grass. (00:30:45)
Visible crew/equipment: After Rick slugs Magnum at the beach, it cuts to Higgins fixing his broken miniature airplane at his desk, then just as the mini airplane collapses onto the desk, a crew member's right hand (presumably he was holding up the airplane's tail) with a ring on the index finger, is visible at the right side of the screen. (00:28:15)
Other mistake: Lee has an Atari 830 Acoustic Modem, which has on its front panel an instructional "cord side" illustration, showing the proper direction for the phone cord when the phone handset is secured in the top two cups. The telephone's cord must be placed at the right side in order for the acoustic coupler to work, but in both Lee's and Magnum's closeups, the phone cord is on the left side, but the acoustic coupler works properly. This is impossible. Also noticeable in closeups is the covered brand name of Atari on Lee's devices. (00:24:20 - 00:27:20)
Continuity mistake: At the hospital, there's a push button desk phone on the table between Lee's and Magnum's beds. There are two closeups of this telephone when both Lee and Magnum lift the handset, and the entire telephone changes to a multi-line desk phone. Plus, in Lee's handset closeup, his hospital ID bracelet changes from narrow to twice the width, and in Magnum's handset closeup, the large floral box of tissues change to a short box of tissues. (00:24:10 - 00:27:10)
Luther Gillis: File #521 - S4-E2
Continuity mistake: At the start, when Luther gets out of his car the license plate number is AUF-365, but after Magnum's visit to the ER, when Luther is at Robin's Nest his plate number is AUF-366. It's the same rented Ford Fairmont Futura. (00:02:40)
Luther Gillis: File #521 - S4-E2
Visible crew/equipment: After Tanaka gives Magnum one day to come up with answers, it cuts to Magnum and Luther in the Ferrari. In the shots facing Magnum, visible on his sunglasses are the reflections of filming equipment equipment directly in front of the windshield, as well as attached to the driver's side door. The device on the door is a bit visible again twice, after they're released from jail the second time, and after Luther's visit to the ER. (00:28:55)
Luther Gillis: File #521 - S4-E2
Continuity mistake: When Luther and Magnum are arrested at Keanu's cockfight location, Luther is wearing his red Hawaiian shirt with palm trees design, then when Tanaka calls them both "walking menaces," the design on Luther's shirt is different now, though it's still the same style. (00:25:50)
Visible crew/equipment: During the flashback, while Magnum is on the longboard paddling five miles to the island, the chopper is flying over the open ocean when TC starts talking to himself about Magnum bucking for a section-8, and as the chopper's nose moves upward the reflection of set lighting, etc, can be seen on the windshield. (00:17:05)