Mr. Gourevitch discussed his book, A Cold Case, published by Farrar Straus Giroux. The book tells the story of detective Andy Rosenzweig's pursuit of an ex-convict named Frankie Koehler. Two men, one a friend from the detective's youth, were murdered in 1970. On the verge of retirement, Detective Rosenzweig, then chief investigator for the Manhattan district attorney's office, decided to reopen the twenty-seven-year-old double homicide case. Mr. Gourevitch's presentation is followed by a question-and-answer period.