Dash Hammett wasn't a very good writer, but he was something of a genius in creating characters that sell. Films with his characters were only successful when heavily filtered through the inventive context of a filmmaker.
Hammett hated it, this messing with his tone. But the original "Falcon" was something of a disaster. Someone had the idea (possibly Van Dyke) of making the Thin Man as a comedy. It was a huge success and has in retrospect been one of the most influential films of the era. So it only made sense for us to see this similar reworking of "Falcon" shortly after the Thin Man's success.
But Van Dyke had a sense of timing and the ability to integrate that rhythm into the whole long form. This poor fellow has no such sense, so the humor is all over the place, each character driving their own bus.
So when you watch it, you have to decide which character to align your perspective with. Though I cannot recommend the picture, if you do see it, I do recommend you become the ditsy blond secretary (who cannot even spell her own name).
She's every bit capable of carrying this movie, where the detective cannot.
I don't suppose she invented the ditz, but it was this girl, here a nineteen year old Marie Wilson who combined a Betty Boop "whoop" to become the sexually available, innocent but hungry, absolutely sweet but terminally dumb blond. Its great fun watching her mouth, a great mouth, one of the era's great mouths managed by an unappreciated master.
The end of the movie is supposed to be something of a tragedy as the Bette Davis character is lost. But because our detective (something of a breezy dolt) has this ready girl to fall back on, the effect is lost.
Ted's Evaluation -- 2 of 3: Has some interesting elements.