There is some debate as to whether Behind That Curtain should be considered an actual Chan movie for collectors.
Technically, it is but Chan comes in so late with such a small part (and part of that is off-screen) that a lot of people who love Chan movies don't even bother with it.
I enjoy it because I like Warner Baxter (who was the reason the studio reworked the story instead of leaving it a Chan story).
Behind That Curtain is also interesting to watch because it's part of the acting transition from silents to talkies.
You have to keep a sense of humor with you because even Warner Baxter still has a tendency in this movie to "chew the scenery." On the other hand, Boris Karloff shows his acting ability (even in a small part) that would later make his Frankinstein Monster famous.
Virginia