The three characters essential to a murder mystery are the victim, the killer or villain, and the detective (or detectives). I read both third-person and first-person mysteries, but prefer to write in the first-person, so our narrator, ex-Navy cop Frank Keegan is at the center of A Halo for Red Betsy; he’s telling the story. For better or worse (as one reader noted, it’s not always fun being inside Frank’s head, but it is always interesting because you never know what to expect.).
Some books on mystery writing advise having, even starting with, a well-developed, diabolical killer, and that is certainly one way to go (James Moriarty and Hannibal Lecter come to mind), but a vague, shadowy killer that the detective much discover also works well. As noted in “Winging It: Our Ever-evolving Mystery Writing Method #1,” we were so vague about the killer that we were able to change him in midstream with no ill-effect (I suspect our villains will become more flushed out as we perfect our craft). Good examples of both abound, so either works well depending on what the writer is trying to do. The killer in The Cheongsam Bombshell, the second Frank Keegan mystery is both more developed, but still hidden, which he or she needs to be in a first-person narrative (Dashiell Hammett’s Red Harvest being a notable exception).
In A Halo for Red Betsy, our victim, Navy Nurse Lieutenant Elizabeth “Betsy” Vale, was killed the night before our narrative begins, and so in one way, was not a character at all (we didn’t use flashbacks, so she had no dialog). Speaking parts notwithstanding, the victim is also central to the story since without his or her death, the detective has nothing to do except gaze at his navel and contemplate the finer things in life. In the case of Lieutenant Vale, as Frank learns of her and her life from those who knew her, he becomes more determined to find her killer.
This is another place where our method of winging it really paid off since when we started, we knew very little about her. We knew how and why she became a Navy nurse, and we knew that she had been killed (though we didn’t know why she’d been killed!). We came to know her when Frank did. In Red Betsy, all who knew her told more or less the same story, though Frank did get sidetracked by one unreliable storyline (this is device I want to exploit more fully in future books).
As with the villain, some books on mystery writing will tell you to develop your victim before starting, but we enjoyed developing the character as we told ourselves the story.