When I see a film based on a novel, I like to read the novel to compare plots and execution. Most of the time the novel or story is fuller than the movie due to the short media time and the target audience. In this case, the novel does have a better-developed plot and is more cohesive. The characters are more true to form and there is a real Rosewood/Rosebrien. However, the book characters are more sinister and Dorothy is sleazy. I planed to make this the last story I would read by Dashiel Hammett. However, others tell me I just picked the wrong one to start with.
The film on the other hand, was modified to give a lighter approach. It is the film that I will think of as the real "Thin Man" and Maureen O'Sullivan as the real Dorothy that was concerned about her father. Speaking about that, what is the Sullivan act?