A comic, grim illustration of one of those unhappier and hopefully unalike families who grew up some years ago under the protective provincial umbrella of the midwest and now return for a reunion in middle to late middle age -- all except a sister who died (of an abortion, as it will be revealed) and a husband (dead by his own hand, by choice?) and a wife (on a happy farm). That leaves strong-minded Phoebe and morally upright, uptight Harrington and charming Thrice who slouched through three marriages and Arnold whose wife Pansy bugs him about the future of their rotten son Arnie. Isolated from the rest of the world on Fire Mountain, they face their ends in And-Then-There-Were-None progression (Mr. Scowcroft reminds you several times of the Agatha Christie original). Only later does he return to earlier events at Fire Mountain where sexual rites of passage, whether humiliating or gratifying, provide the delayed fuse behind the latterday reparations. . . . A minor success since Scowcroft has chosen to play his hand so that curiosity must succeed where sympathy obviously hasn't got a chance.