In 1981 Christopher Lehmann-Haupt, reviewing Mooney's first novel Easy Travel to Other Planets ( LJ 9/15/81) in the New York Times , noted that, ``When Mooney relaxes a little more, something first rate is likely to result.'' Unfortunately, Mooney still seems a bit tense. Not that his second novel is devoid of merit. But because it tries so hard, its dramatic edge is dulled (as is its eroticism). The story has intriguing possibilities. Based on a rewrite of history, it involves diplomatic maneuvering undertaken to prevent a test of the first atomic bomb while using the threat of just such a test to induce an end to South African apartheid. Caught in the midst of the wrangling are the daughters of two of the diplomats--plus a Hollywood special effects genius, a South African rock band, and a ghost-cum-intelligence agent. Because the book has all the elements of a best seller, it is too bad that excess verbiage obscures the novel's vision that the simple, random act often has the greatest impact on humanity's destiny. Interesting but overwrought. For general audiences.-- David W. Henderson, Eckerd Coll. Lib., St. Petersburg, Fla.