If a writer really wants to sell a lot of books, the surest route is to establish themselves as a brand, and then deliver exactly what readers expect, over and over again. There can be some variety. Not every James Patterson or Stephen King or Colleen Hoover book is exactly alike, but they share such similar DNA that a reader knows what they’re getting.

This is not the case when I pick up each new book by one of my favorite working writers, J. Robert Lennon. Each new reading experience has some element of surprise.

Lennon’s most recent book is “Hard Girls,” which is billed as a crime novel, and it is that, but it’s also a family story, a coming-of-age novel and maybe even has a hint of satire about the crime novel genre. It tells the story of Jane and Lila Pool, fraternal twin sisters raised by an absent-minded professor and a dynamic, but frequently absent mother who is maybe off having affairs, or is a spy, or something else entirely. The novel alternates between Jane and Lila as teens, essentially raising themselves, ultimately getting into real trouble, and Jane and Lila as adults, Jane with a husband and young daughter, trying to put her youthful trouble behind her.

But after years of no contact, Lila has summoned Jane using a spy code of their own invention from childhood. Lila says she may know where their missing mother is. Jane cannot resist the pull of maybe finding out the truth.

The big-picture plot of the novel unspools to the expectations of the genre .