Plot hole: Magnum finds the cat with the bloodied paws. He takes the cat home, arranges with Higgins what to do, brings it back where he found it, and tails it for "over an hour", Higgins says. Finally finds where it came from, and in the house there's a corpse. Shenanigans ensue, Magnum comes back with the police to a now empty house and he tells to Katsumoto that it was not empty "a couple hours ago" and is amazed at how quickly and efficiently the bad guys must have cleaned. The problem is; later we see through the security cameras what happened, and how Max the cat got the blood on its paws. Supposedly the villain did an ultra-efficient job cleaning everything up after Magnum's visit...but what about before? Magnum arrived a good 2 hours after the homicide. What on Earth did the killer do during that time? The dead guy was still lying around in a pool of blood, and the bad guy hadn't even picked up his own ski mask! Forget it. He did not even close the front door.
Other mistake: During the game at the beginning of the episode, the opposing team (the Pearl City Chargers, white and purple) fields at least two players with the same jersey number 12. The kid protagonist runs past a guy with number 12 at he starts his run, and then dodges another two in front of him, who are present in the same shot - it's not a matter of editing/continuity, at least in that second shot. (00:50:00)