This is actually THREE classic short novels, rather than two. The first two are tales of "The Spider", the kind of hero whose stereotypes are Doc Savage or The Shadow, a man whose public face is "idle rich", but by night...
The first story, SATAN'S MURDER MACHINES, finds the Spider dealing with the Robot Titans of the title. Giant walking machines which kill and ravage the city with impunity, thwarting all efforts to stop them. This story absolutely stunned me with the amount of thought and planning that went into it. I won't reveal the machine's secrets here, but I will say that Page was dealing with concepts that wouldn't re-appear in science fiction for almost thirty years, and he made the machines both believable *and* workable. Fun.
The second story, DEATH REIGN OF THE VAMPIRE KING, we find the Spider dealing with a villain who uses swarms of bats, augmented with poison fangs, to terrorize the city. The Spider ends up framed for the murders and must both catch the killer and clear his name. The aerial combat scenes were splendid, and I liked the fact that Nita, the Spider's girlfriend, is drawn by the author to be just as skilled and tough-minded as the Spider.
The final story, THE OCTOPUS: THE CITY CONDEMNED TO HELL, was a one-off that apparently never gelled as a series. It deals with "Dr. Skull", a skilled and dedicated young physician, who disguises himself as old, and fights crime and evil wherever he finds them. Here, he must deal with "The Octopus" an evil both ancient and young, who turns people into monsters to feed his empire. It's not quite up to "The Spider", but it was fun to read.
Add in cover *and* interior art by Steranko, and you've got a recipe for solid entertainment. The book also lists another volume "The Spider: City of Doom" in the works.
This was a heckuva lot of fun to read, so all I can say about the prospct of another volume is: Goodie!