Early days in Norbert Davis' writing career, I think, and written for the "pulps." Characters are flat, not real people at all. Plot was kind of rickety but some of the dialogue was fun. Davis developed Doan's character more as years went by (about 5 stories by Davis on manybooks.net as I write this, last one copyrighted 1943). Other characters also became a little more rounded, and his female characters are very well done. Doan will be a stronger, more individual character in the later stories, and Carstairs gets MUCH more room in the later stories. Here, he's mostly a gimmick.