According to some soothsayers a resurgence of social significance in the rts is imminent; if so the chronicle here of Broadway in the Thirties should be handy indeed. But, we might add, only as a yardstick of what not to do, for nothing seems quite so dated, so done-and-gone as the leftist theses and cultural tempers these pages explore or explode. And that includes everything from the Communist arty's own tropes (Marxist jingles: And the bosses quake with fear/for the worker's ay is near) to the multifarious middle-of-the-roader variations in the Federal Theatre, the Group Theatre, the Theatre Guild etc. The Party Line switcheroos as executed by the Daily Worker and New Masses critics (first the call to arms and Fight Fascism, then after the Russo-German pact, the short-lived Keep Peace alaver) are obvious enough, but even the ""major"" plays seem simplistic, schematic period pieces (Odets' slambang Waiting for Lefty; Idiot's Delight; Dead End; Bury the Dead; Cradle Will Rock; Pins and Needles). Ironically enough, that era's only offerings capable of withstanding a sophisticated scrutiny are the plays of Bertolt Brecht, all instant flops then, all ""classics"" now. A well-researched, if rather workaday account, of what happened during the Depression days when to be ""in"" meant following the Leninist dictum: Art is a class weapon.