The biggest mystery is why the Lindsays don't connect their trailer's pulling to the right, and frequent inspections for contraband, with the strangers following them. Instead, Lisa worries that she'll lose a journalism scholarship because her parents won't settle down (this time it's Oregon to Mexico), and she wonders why Grant Meredith, who is driving his grandmother (in a Packard!) on the same road, is so aloof. Young wanderlust parents (retired Navy--thus ""starboard"") show little interest in her plans for the future; then a road accident brings the Merediths, the police and the recurrent mystery men rushing to the scene of gold bars dropping out of the trailer bottom. Highway robbery if you expect a mystery, slightly more acceptable as a start-of-summer diversion.