Continuity mistake: When the load of lumber is dropped on Captain Greer's 1968 Ford Galaxy 500, the car turns into a beat-up 1960 Oldsmobile just before it is squashed.
Continuity mistake: 9-4 "Man on Fire": McGarrett's blackboard already lists plutonium as the poison source before Dr. Ormsbee enters to inform him that plutonium was the poison source.
The Baranoff Timetable - S2-E21
Continuity mistake: Ortega takes Mundy's shoes (with lock picks hidden in the heels) and locks him up. Mundy soon has the confiscated shoes back on again, though, even before he escapes the cell. (00:40:00)
Continuity mistake: The unit says 1w20 then later says 1w30. (00:25:40 - 00:26:40)