In 1944, a charismatic young Swede volunteered for a desperate mission to save Budapest's Jews, the last substantial population threatened by the Nazis. Posted to the Swedish Legation and provided with ample funds and authority to do whatever worked, Wallenberg issued documents verifying trumped-up links to Sweden, set up ``safe houses'' under the Swedish flag, organized support from other neutral legations, threatened Hungarian officials (caught between Eichmann's brutality and the war's imminent end) with records of their acts, and used his commanding presence and sheer willpower to whisk Jews from assembly points and loaded trains. Then, perhaps imagining he was a spy, the Soviets entrapped him; despite numerous alleged sightings, his fate is unknown. Acknowledging extensive use of archival materials and interviews with people who knew Wallenberg, LinnÇa laces the story with dialogue, noting that ``the thrust of each conversation...has been documented.'' Her style's undistinguished, but the events are truly compelling, and she does a good job of sorting out the complex dynamics of those terrible days. The b&w photos, many taken secretly at the time, are also of interest. Milton Meltzer's lucid and powerful 12-page view of these events in Rescue (1988) includes some telling facts omitted here; still, this dramatic longer account is welcome. Index. (Nonfiction. 11+)