Richard Stark's Parker and Garry Disher's Wyatt are a case of literary tribute and possibly symbiosis like none other that I know. Parker, created in 1962, is a prototypical professional, an unsentimental planner of elaborate capers who kills only when necessary but does not hesitate to kill when he must. So is Wyatt, created thirty years later.

Each is identified only by his last name. Each is harassed by the mob, which is called, in both cases,…