Major Thorpe (writer and artist), Mort Leav (pencils and inks)
Published in Jumbo Comics #35, Jan 1942 - 8 pagesZX-5 has come to an undisclosed town to deliver an important message to an envoy. Someone does not want him to succeed as they send a package with a snake in it and follow it up with a cowled female assassin. His way of hiding the message is a bit unorthodox.
Here are the pages I have of it.