I'm not sure if it is a spin off or not, but what I found interesting is the similarities (whether intended or not) between this new show and the Aussie show Miss Fisher's Murder Mysteries that first aired in 2012. If you haven't seen those give those a look. I adored that show and the spunk behind the characters created. Here is a quote from Miss Fisher "Our female sleuth sashays through the back lanes and jazz clubs of late 1920s Melbourne, fighting injustice with her pearl-handled pistol and her dagger-sharp wit."

i have seen miss fisher and really liked it. i think i read somewhere that they are trying to do a movie to close it out