Ron "Planner" Preston has enjoyed a long criminal career out of jail. Caution, if anything, has been the key to his success. So a payroll van with a predictable route and minimal guard looks like a quick easy take. When the truck's schedule is abruptly changed and its guard doubled, however, Preston much either abandon the plan altogether or take on some young and risky new recruits, ones who may consider his habitual wariness a sign of the timidity of old age.Harpur and his boss, Assistant Chief Constable Iles, are accustomed to keeping an eye on men like Preston, not so difficult a task in a milieu where cops and criminals meet on many levels: professional, familial, social. Therefore, they are quick to take notice of increased activity surrounding "Planner" on the part of his family and associates. But how are these moves to be interpreted? And where is the line between certainty and conjecture to be drawn? As one criminal aptly observes, "Chance matters."