Case not affair--the title indicates the difference from Betty Schechter's fine treatment of a few years ago, the text provides a vital alternative to her more measured tone; in coverage, one complements the other. Dreyfus is being returned from Devil's Island to face a second trial; incident by incident, conspirator by conspirator, conversation by conversation, Mr. Werstein traces the events leading to his downfall, with special attention to the military background of each and a candid appraisal of anti-Semitism in France generally. The result is akin to good crime writing, with a similar punch and considerable suspense, but without melodrama or distortion. Less attention is paid to the broad repercussions and ramifications than in Schechter. For fast, involving reading Werstein has the edge; for balanced history Schechter is better--both are responsible and significant.