Revealing mistake: In the night shootout, Magnum cocks his pistol in a close-up that is obvious performed by a trained stunt double. Whoever is doing this is wearing the same clothes Magnum has but with the T-shirt in pristine condition straight from the washing machine, while Tom Selleck just took a dive in the dirt. Moreover, he wears the team ring upside-down. (00:22:50)
Revealing mistake: When the bandit holds Adelaide and then drops her off the horse, you can get a good look at the face of the person, and it's a younger stuntwoman, not Christine Belford. That stuntwoman has to roll in the dirt and get up, but Christine Belford emerges in the next shot without a speck of dirt on her shirt's sleeves nor the back of the jeans that got all soiled earlier. (00:14:45)
Revealing mistake: Magnum and Adelaide are headed to her place on TC's chopper. Throughout the sequence, the camera moves up and down but can't conceal that the fact that they are not moving at all and they are just sitting in the chopper, with set lights reflected in her glasses and even the silhouette of the rotor of the chopper, completely still, peeking through the glass. (00:04:50)