Harsher in Hindsight: The film depicts Bruce battling his family demon to protect his son Brandon. Brandon Lee would die from an accidental gun discharge during the making of The Crow a few months prior to this film's release. Making this worse is the fact that Brandon turned down the opportunity to play his father, opting to do The Crow instead.
Misblamed: The scene depicting Kato as a relentless one-man wrecking crew while the Green Hornet sits helplessly tied to a chair and blurting "Good job, Kato!" in a pathetic attempt to make himself seem relevant. While not accurate to the actual show at all, it became pervasive enough that most people remember it as being that way, apparently including the people who made the modern The Green Hornet movie.
Nightmare Fuel: Your Mileage on the demon, but the part where he shows Bruce his own grave is scary in it's own right. Genius Bonus when you notice it doesn't just show the date that Bruce died in real life, but that is an accurate replica of his Grave with Lee's actor replacing Lee in the photo.