Peril by Post

The eighth book in the series finds John Pickett bound for England's scenic Lake District, where an unsigned letter has summoned him for an unspecified reason. Posing as a honeymoon couple, Pickett and his wife Julia, the former Lady Fieldhurst, take a room at the Hart and Hound as the letter instructs him. Once installed there, however, Pickett can do nothing but wait for the anonymous contact to identify himself. A midnight search of the inn's register seems to identify the innkeeper, Ned...