Superman moves from a quarterly to a monthly with issue 6 (Sept/Oct. 40).
Lois Lane goes to do a story on a jewel collector with a high security (for the period) house, but winds up accused of his murder, in this story by Siegel and Cassidy.
The story introduces an aggressive reporter for the Morning Pictorial, Scoop Carter, who thinks nothing of pulling out the telephone lines to prevent Clark from phoning in his story to the Daily Planet. As well, Sergeant Casey debuts in this story, and will be a regularly appearing character over the next few years.
Casey arrests Lois for the murder, but Superman is convinced of her innocence. But every bit of evidence he finds seem to implicate her even further. This story shows that Superman has what will later be called microscopic vision, which he uses to see fingerprints. He also demonstrates his super-memory, as he can tell Lois’ fingerprints by sight.
But Superman persists with the case, even though this puts him into conflict with Casey. Finally, he finds a hidden camera in the house, and finds proof that the architect was the real killer, and the one who framed Lois.