Author Sue Grafton has promised to write a mystery for every letter of the alphabet. She started her series with "A is for Alibi" and has just published her 16th- "P is for Peril." The latest book pits heroine Kinsey Milhone against a bitter ex wife, troubled children, a shady business partner, and a suspicion of Medicare fraud . Grafton told Minnesota Public Radio's Greta Cunningham that her main character is the key to her success: