Mystery buffs will find Hetty Wainthropp to be delightful and uniquely entertaining company. Hetty has just turned 60, but she is not about to "ride serene into the evening tide," as her doting husband so poetically puts it. "I'm not 60 and I never will be," Hetty proclaims. "I'm not a senior citizen." Hetty wants to matter, so she gets a job at her local Lancashire post office. But that wouldn't ...