A day after gunning down Dave Cairnes’s criminal rival, Bob Jenner, the assassin, one John Doe, is escaping after a night of hired, heightened sex when his driver accidentally hits and kills young Simon Kerr. There’s no question of stopping, of course; the pair of them could never explain to the coppers what they were doing in out-of-the-way Clevestone. But an elderly witness to the accident gets their license-plate number—or does he? Fresh-faced PC Geoff Ballard, questioning the witness, realizes that somebody’s already visited him in an attempt to muddle his shaky memory. A member of Cairnes’s gang? A crooked cop? When the case peters out for lack of evidence, Ballard decides to pursue it on his own, confronting his boss, making inquiries on bogus authority, and leaving himself vulnerable to the oldest temptation in the book, unaware of something every fan of Ashford’s ethical-challenge suspensers (The Cost of Innocence, 1998, etc.) will have known before page one: He’ll end up swimming in murkier moral waters than his Boy Scout code has ever prepared him for. Neatly turned, with nagging questions remaining tantalizingly unresolved for most of its length. Only in the finale, when the criminal rounds on Ballard with a hollowly ironic self-defense, does Ashford’s crisp plotting sag.