Batman is back on the cover for Detective 35 (Jan 40), but the picture seems to show him fighting the Duc D’Orterre, from the previous story.
Batman clearly has no problem with guns at this point. Oddly, this story, by Bill Finger and Bob Kane, does not have Batman involved in any big gun fights.
The story all deals with a stolen ruby idol, and a very mysterious murder. Commissioner Gordon, who has not been in the last few European stories, is back in this one, in a very small role.
The one significant development in this story is the car. Still not a Batmobile in any sense, this “high powered roadster” is now blue, matching the highlights in Batman’s costume, personalizing it a bit.
In this issue, Steve Malone gets a secretary, Nancy. He sends her out as bait for a kidnapping ring, and though she gets freed, we never see her again, and it wouldn’t surprise me if she gave her notice after that.
Jerry Siegel sends Slam off to Africa to hunt down murderers in this issue’s tale. Slam and Shorty wind up enlisting in the French Foreign Legion in order to find they prey. One of the men they are hunting winds up being their sergeant, so the usual tale of the brutality of the Foreign Legion gets used as an attempt to kill Slam.