No mystery why PBS series is so successful

Readers of mystery novels know and revere the name P.D. James, and "Mystery!" fans rejoice when one of her psychologically complex tales airs on PBS.

With good reason.

Ms. James's poetry-loving detective, Adam Dalgliesh (Roy Marsden), is a bright, benign, gentlemanly fellow. In fact, all of James's characters, heroes and villains alike, are complex enough to matter to us - it's hard to despise even the guilty among them, because they all have sad secrets.

Take the three-part puzzler "A Certain Justice" (Part 1 airs April 15 at 9 p.m.). The carefully constructed tale involves a brilliant barrister, a criminal lawyer named Venetia Aldridge (Penny Downie, "The Ice House") who has everything going for her except human kindness. She is a terrible mother, she defends bad men who are guilty, and she runs roughshod over her cowed colleagues.

When she winds up neatly dispatched, no one cares much except her neglected teenage daughter, Octavia (Flora Montgomery). Riddled with guilt, the poor kid has fallen in love with her mother's last client, Gary Ashe (Ricci Harnett), a nasty young man with lethal tendencies.

But the ill-tempered young Mr. Ashe is not the only suspect - nearly all of Venetia's colleagues have a motive, if not necessarily the will, to do her in. She had threatened to terminate one career, stifle another, and expose a lover to his wife's wrath.

Every one of these characters is complex enough to win our interest - including the abrasive victim herself. Most of them have suffered some grave injustice in youth or childhood that helps explain their present behavior - explain, but not excuse. James makes them fully human so that we understand them and also see their faults.

"P.D. James is a profound woman, well-read and well-lived," says Rebecca Eaton, executive producer of "Mystery!" "She has had a hard row to hoe in her personal life, and I think she has learned a lot about human nature."

James named her first child, Jane, after Jane Austin, whom she admires for the way Austin structured her novels and "for her cool moral tone, which I think [James] shares," Ms. Eaton says.

"James profoundly feels the absence of morality in our culture, and these [mysteries] are her way of writing about it."

Even her choice of settings - churches, law offices, a publishing house - points to her concerns about the state of the culture. They are "safe" places that have been upset by disturbing outsiders, lost souls. Or by insiders with some deep emotional wound suffered long ago that comes to light in the story.

James's compassion is part of her moral sense. And while they are never moralistic, James's stories always have a moral sense about them, Eaton says.

But then, that's one of the secrets to the success of the "Mystery!" series - all or almost all the stories have a quiet center of moral calm amid the tempest of crime and passion - usually in the person of the policeman or the private eye who solves the case.

Now in its 19th season (Eaton has been involved for 14 years), the series appeals primarily to the over-50 demographic - well read, well educated, and comfortable people who enjoy a good puzzle.

"Our philosophy has been to choose the well-told intellectual or psychological puzzle rather than bloody murder or action-adventure murder. We are more interested in how people got there and then what they do afterward," Eaton says.

Not that ghastly crimes aren't committed on "Mystery!" "But we are judicious. You'd be surprised what we turn down." Sensational or humiliating crimes graphically told are assiduously avoided.

About half of the stories are obtained from British TV, including the BBC. The other half Eaton co-produces with various British companies. She speaks for herself and her viewers when she describes the attractions of "Mystery!":

"I love the actual day-to-dayness of how [the crime solvers] plow through the information they have ... then trust their instincts and prevail. You form an attachment to [the crime solver] as they struggle through their day - and then they have their concrete reward at the end of the hour."