"Yellowface" roles
Here are some bad examples of non-Asian casting of Asian characters on the show. Unfortunately I don't have the episodes listed in the S[eason]01E[pisode]01 type of format on my WWW site yet (after 20 years!).
A bit of trivia, by the way (I have told this story before). Many years ago, I had lunch with James MacArthur when he was in Vancouver making a movie. I asked him about the use of white guys to play Asian parts like the guys below. This was not a good idea, he got very annoyed, starting out with "Oh, it's that 'if you see Kay-ing' political correctness again..." (yes, Danno actually used the word 'if you see Kay-ing'. This was pretty embarrassing, as I attempted to let him know that I wasn't trying to unleash some sinister PC agenda, but just wondered why no one had considered using real Asian actors to play these parts -- I'm sure there were SOME such actors around at the time. I guess he really wasn't that mad, since he paid for my lunch.
(I am making a substitution for the bad word above not because I am trying to be politically correct, but because IMDB will censor that word if I type it out normally.)
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Season 01. Samurai
Ricardo Montalban (seriously - Khaaaaaaaaaaaaan!!!) plays Leonard Tokura, "head of organized crime in Hawaii." Montalban, who was a Japanese kabuki actor named Nakamura in the film Sayonara, gives a bizarre performance which is suitably dramatic, and his repartee with McGarrett is delightful. However, his "yellowface" makeup is silly, and his mannerisms are annoying, including the way he smokes a cigarette like Arte Johnson's Laugh-In character.
Season 01. By the numbers
The very white Will Kuluva plays "big brother" Philip Lo in this episode -- his makeup is hideous, and looks like the Asian equivalent of "blackface." (His son is played by Randall Kim, who was born in 1943, so he was around 25 in 1968. Kuluva was born in 1917.)
Season 01. Face of the Dragon
David Opatoshu does an Alec Guinness playing the Asian patriarch Shen Yu-Lan (badly -- but not as bad as in #83, A Matter of Mutual Concern).
Season 02. To Hell with Babe Ruth
I have no idea why the producers chose Mark Lenard (of Star Trek fame) to portray escaped mental patient Yoshio Nagata -- he doesn't fill any of this bill with his jerky movements, hideous orange makeup (in some shots he looks more like a burn victim) and terrible accent (when he speaks Japanese, even my Japanese wife had difficulty understanding him). However, he pales in comparison (no pun intended) beside Will Kuluva as Yuko Takuma, the Japanese clock shop owner. Kuluva already appeared in Asian guise as Philip Lo in S01E09, By The Numbers, an equally wretched performance.
Season 02.Which way did they go?
Philip Pine plays Toshi Nomuru, boss of the exchange -- his Asian makeup is ghastly.
Season 03. The Late John Louisiana
Alfred Ryder plays the Fu Manchu-moustached Asian Quon, who is into "gambling, prostitution, smack, shakedowns" according to McGarrett, and is just passable in this role because of his grubby demeanor.
Season 03. The Gunrunner
Local "businessman" Bajano, who is very sleazy, is played by Philip Pine, who had experience in Which Way Did They Go, playing another "Asian" (as in this episode, not particularly well).
Season 04. A Matter of Mutual Concern
David Opatoshu appears as gang boss Li Wing. Unlike in Face of the Dragon, where Opatoshu, also doing a Peter Sellers and pretending to be Chinese, was given some moderately passable makeup as well as Chinese dress, here he has no makeup at all, aside from his white hair. Trying to accept this guy as Asian really pushes "suspension of disbelief" into another galaxy. This episode features several racist words *beep* Jap, *beep* though they are all uttered by "ethnic" characters.
Season 04. Is This Any Way to Run a Paradise
Richard Morrison, who plays the Asian Lai Han, appeared in the previous season's episode The Last Eden, also an ecologically-themed show. There he played a (white) professor. He also plays the white warden of Oahu State Prison in the NEXT episode.