Plot hole: 8-22 "Love Thy Neighbor, Take His Wife": The police cars speed to Tanaka's house with their sirens screaming, warning him in plenty of time to allow him to escape. Apparently these guys never heard of the law-enforcement standard "silent approach."

Visible crew/equipment: 8-16 "Legacy of Terror": As an HPD cop escorts the old man out of McGarrett's office, he trips over a camera cable and nearly falls. When the actor recovers his footing and finishes his exit, the cast regulars simply pretend it never happened and go on with the scene.

Deliberate "mistake": 8-4 "Target? The Lady": During the car chase, a crowd of real-life tourists is standing on the sidewalk, very obviously ogling the film crew as they shoot the scene. The footage was left in to avoid an expensive retake of the stunt chase.

Plot hole: 8-22 "Love Thy Neighbor, Take His Wife": McGarrett has two unexplained clairvoyant moments in this episode. First, he divines that the Indian-style headband is turquoise without seeing it. Then, after the kidnappers' phone call proves untraceable, he somehow knows that it was made from a specific pay phone.

Factual error: 8-12 "Honor is an Unmarked Grave": Marshall has been in Hawaii for only 3 weeks, yet he has his cat, which he brought along, living with him. Hawaii requires a 4-month quarantine on all pets brought in from the mainland. Marshall's kitty should still be in lock-up.

Revealing: 8-5 "Death's Name is Sam": The plane hit by the missile is a little too obviously a still photo with the explosion superimposed over it.

Continuity: 8-13 "A Touch of Guilt": The assault is said to have occurred at the Zanza Bar. But when we see the location, the bar is called The Makai Lagoon Club instead.

Continuity: 8-9 "Retire in Sunny Hawaii - Forever": When Danno leaves his car, he's wearing a brown suit, but he enters Ellen's office wearing a black one.

Continuity: 8-15 "Deadly Persuasion": Danny says he hasn't fired his old 45 automatic "since I got out of the service." But at least two previous episodes had established that he joined Five-O right out of college, and was never (not even before college) in the service.