Robertson (Paradise Falls, The Greatest Thing. . . trilogy) is a writer of definite talent and erratic performance, and here are 416 inconclusive pages of rich, strong, funny, poignant writing that testify to both. The setting is again Paradise Falls, Ohio, where ""comely"" (her favorite word) Miss Margaret Ridpath, who is ""to the world what tinfoil is to iron,"" will die heroically at 63 in 1974 (the day after Nixon's resignation) in a gun-battle with a trio of Manson-style bankrobbers. That triumphant death (""Hey! I am not afraid!"") will come after 40 years of caring for her gross, nude-rambling, incoherently sly mother; after 30 years as a weekday ace bookkeeper and weekend touring bridge champion; after 40 years of virginity and then 23 years as the mistress of, first, a Jewish dentist and then (when Irv Berkowitz dies in her arms in London) her randy, widowed brother-in-law. Robertson tells us about other lives too--about the women who help to care for Margaret's mother: Wanda Ripple (served 1939-1960), who believed that love killed her two husbands and therefore kept Mrs. Ridpath alive with lively displays of hate; and Pauline Jones (1960-?), whose doomed, frustrating decade of romance with a hopeless transvestite turned her from Homecoming Queen into sawdust, the only human being more afraid of the world than Margaret. These life histories enhance the Ridpath chronicle, as do, in a gruesome way, the masochistic, ritualistic minutiae of Mother Ridpath's dementia. But Robertson loses control and moves into tracked-up territory when he gives us elaborate psychological backgrounds and explicit sexual traffic directions for the adolescents who die in the shoot-out with Margaret--and this whole finale concept is too pat-symbolic and too puppeteerish for a people writer like Robertson. Margaret and Irv and Wanda and Pauline and the others are significant enough without turning them into factors in an equation about old virtues and new vices.