A good question. For me, the focus is on the Charlie Chan SERIES, that began with "Charlie Chan Carries On" in 1931 and ended in 1949 with "The Sky Dragon." "Other Chan films are interesting, and sometimes worthy, in my humble opinion, but, it was with the series proper that the charlie Chan as we know him existed as a serious, main character.
"Eran Trece" is an interesting case. As it was made by the same film studio that made the original film upon which is is practically a mirror image, "Charlie Chan Carries On," it can be argued for inclusion as a bonafide Charlie Chan film, or at least a window through which we can get a good glimpse of the "parent" film.
