Since his mother is taking computer courses for two months, Mark is stuck, one afternoon a week, with shuttling his small sister to the house of her new Russian friend, Natasha Zhavoronkov. Mr. Zhavoronkov is one of a group of scientists working temporarily at the lab where Mark's father is employed. Mrs. Zhavoronkov and Mark quickly become friends--he likes hearing about Russia and helping her learn English. But he can't shake off his suspicions about the family, especially when he sees them passing documents to another Russian. Of course, there are misunderstandings: Mark (egged on by a friend who clings to the lingering rhetoric of the Cold War) is wrong. But despite an author's note on the difficulties of writing this amid the recent changes in Soviet-American relations, the book feels dated. With bland, one-dimensional characterizations, McLerran fails to challenge readers' assumptions and provides too little, too late.