The pressing social problem of illegal immigration is the concern of this present-day story of courage and conflicting loyalties,"" reads the flap copy; it is also, predictably, the book's chief selling point. We first spend a great deal of time in the Mexican fishing village of Ensenada, learning why 13-year-old Lupita Torres (""Lupita Manana"" because she thinks each next day will be better) and her 15-year-old brother Salvador are sent off to ""rich"" Aunt Dorothea, in California, to find work. We spend considerably more time learning about their difficulties reaching Tijuana and getting across the border--finally, hidden in fruit-crates. Then, with the ever-present danger of deportation by la migra (the immigration authorities)--which makes the youngsters especially prey to exploitation--the incidents take on an urgency and the particulars (of working as a menial, or in the fields) have their own interest. Aunt Dorothea turns out to be on welfare, and the whole family is unwelcoming; Salvador ditches Lupita for new, flashy friends; and she perseveres, miserably. At the close she is alone (Salvador, caught by chance in a raid, has been deported)--plotting to be independent, gamely learning English. The wetback situation is thus handled realistically--a long note explains that Lupita and Salvador are ""real people""--and, once it crystallizes, inescapably involving; but the preliminaries are very long and the characters are merely conveniences.