Mr. Was

Ingenious plotting and startling action combine to make this time-travel thriller a riveting read. Trying to escape from his violent father, Jack and his mother move into his late grandfather's mysterious house in Memory, Minn. There, the 13-year-old discovers a door that can hurtle him 50 years into the past. In the present day, Jack's father is rampaging: he calls the boy's mother a ""hardheaded bitch,"" breaks her fingers and eventually kills her with a baseball bat. Jack escapes through the time-travel door, planning to wait 50 years and prevent the crime. Unbeknownst to him, he is becoming entangled in his own family's ugly history: past and future are irremediably entangled. Jack's strange destiny takes him from the bloody battles of WW II Guadalcanal to a government-run mental institution, where he suffers amnesia and a drug-induced type of catatonia. The only real flaw in this feverish page-turner is the pedestrian heaviness of the dialogue. Hautman, the author of three adult novels, can otherwise be commended: his structure is sophisticated without ever overwhelming the reader, and mined with surprises that explode like fireworks. Ages 12-up. (Oct.)