And it isn't just Asian actors. I'm Italian, and I've played pretty much all over the Mediterranean and a good chunk of Latin America.

The veteran television actress is Chinese American but the role she may be most remembered is Keiko O'Brien in Star Trek where she played a Japanese. Then there is AfterMash where she played a Korean and Last Flight Out where she played a Vietnamese. Asian actors and actresses play other ethnic Asians all the time in Hollywood.

I may be wrong, but I think James also showed up on MASH playing a Korean gentleman, too.

Please tell me what it is about James Shigeta's performance that tipped you off that he is of Japanese descent and not Chinese (he's a Hawaii-born American, by the way). Did you know beforehand who he was?
And why is it wrong for Japanese to play Chinese anyhow? They are of different ethnicities and nationalities, true, but they are of the same race (Mongoloid). Should actors play only roles which match their race, ethnicity and nationality?
I agree that an actor playing a different race can easily go awry (i.e., Mickey Rooney as a bucktoothed Japanese or Al Jolsen in blackface), but there was nothing offensive about James Shigeta's performance at all.

Even as recently as 2005, the Japanese-set film "Memoirs of a Geisha" had 3 Chinese actresses play the leads.

You think that's bad? I've been watching some of the Charlie Chan mysteries of the 1930s, and let's just say that the African-Americans in these movies weren't exactly shown in a very positive light. I'll just leave it at that.
As for "The Judas Tree", it's a great episode and I love the fact that Ellery has a couple of open shirt moments in it.
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Jim Hutton: talented gorgeous hot hunk; adorable as ElleryQueen; SEXIEST ACTOR EVER