Wildly popular mystery writers Jonathan and Faye Kellerman may be the country's best-sellingest married couple, but their lives aren't exactly glamorous. Time is short when you're each writing about a book a year while raising four children, ranging in age from 2 to 16. ''We have an active social life, but we're not the types to appear in Vanity Fair or do amaretto ads,'' says Jonathan in their sunny Beverly Hills home. Adds Faye: ''I have to schedule my writing time, and that forces me to be disciplined.''

Still, as their many fans know, the Kellermans' idyllic home life doesn't prevent their novels from straying into the darker side of human nature. Jonathan's books follow the adventures of child psychologist Alex Delaware as he solves mysteries with an alienated gay LAPD detective. Jonathan, a child psychologist, draws on his years working with ailing kids at Children's Hospital of Los Angeles. Faye has staked out different ground: Her crimes are solved by Peter Decker, a homicide cop in northern L.A. County who's made a difficult transition into Orthodox Judaism, with input from his Orthodox wife, Rina. Faye's tales never stint on gory details — a technique that carries a surprising emotional impact.

This year Jonathan published a children's book, Daddy, Daddy, Can You Touch the Sky?. It's the perfect counterpoint to his upcoming Self-Defense, in which Dr. Delaware treats a young woman who dreams of a murder involving her father — or Faye's just-published Sanctuary, in which Peter and Rina investigate the murders of diamond dealers. ''We find a lot of people who write strong novels are extremely mild people,'' says Jonathan. ''I guess that makes a certain sense. We write about the things that trouble us.''