This book is a double story collection from the Collected Works of Agatha Christie by Heron Books. The stories are: 1) Sparkling Cyanide; and 2) Partners in Crime. Sparkling Cyanide, also published as Remembered Death: It's been less than a year since beautiful heiress Rosemary Barton took her own life during a birthday dinner in her honor. Her husband George never believed that his fun-loving wife would kill herself. The truth will out....Partners in Crime: Tommy and Tuppence take over a detective agency and assume the methods of such great fictional detectives as Sherlock Holmes and Hercule Poirot to solve case after case.