Continuity mistake: As Kono talks to Johnny Kalama in the students' apartment, an orange lava lamp sits on the shelf between them. Each time the camera angle reverses, the wax bubbles in the lamp are very noticeably in different positions and configurations. (00:41:00)
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.
Audio problem: When McGarrett and Danno pull away from the curb in McGarrett's big black Mercury, the tire-squealing sound effect begins before the car actually starts to move. (Doesn't happen unless you're flooring it and "peeling out," which they're not.) (00:41:50)
Factual error: Danno, who's posing as a Marine, has hair that's far too long to be permitted in the Corps. In fact, all of the Marines in this episode have non-regulation (too long) haircuts. 'T'was the same then as it is now: US Marines are given "buzz jobs," and hair longer than an inch is not allowed.
Plot hole: McGarrett is hunting for heroin dealers who've laced the drug with arsenic. Yet when he and Chin Ho arrest Harry Parch and find his stash, McGarrett performs the TV cop cliché of sticking his finger into the white powder and tasting it. Even that small a dose of arsenic could be lethal, and seasoned cop that he is, McGarrett would know that. (00:29:30)
Factual error: Don, who professes to be a Buddhist, chants in the jail cell and refers to Buddha as "god." Adherents to this religion do not worship the Buddha and never refer to him as god. Later on, Don chants to Krishna, a Hindu deity not even remotely connected with Buddhism. So, just what is Don - a Buddhist or a Krishna? (00:12:30)
Continuity mistake: Danno, posing as a photographer on the beach, snaps the shutter at a bikini-clad girl and quips, "I only wish I had some film." Seconds later, he takes a picture of the suspects that's then used to identify them. The scene is continuous, and at no time did he ever load film into the empty camera, nor did he have another one. (00:34:30)
Factual error: Throughout this episode, the Japanese assassins are inaccurately referred to as "the Bushido." They should, as the episode title implies, be called Samurai. Bushido was the revered code by which Samurai warriors lived, but was never an appellation for them. (00:17:30)
Continuity mistake: The HPD snipers watch McGarrett's office window, trying to get a clear shot at Collins. In camera views from inside the office, there's a coat rack with a hanger on it standing in front of the window. But in all the shots from the snipers' POV, the coat rack isn't there. (00:40:00)