In the mid-1970's, a homely, friendless Australian girl of 8 picks a name out of a Manhattan phone book and writes to him; she includes a chocolate bar. She's Mary Dinkle, the only child of an alcoholic mother and a distracted father. He's Max Horowitz, living alone in New York, overweight, subject to anxiety attacks. He writes back, with chocolate. Thus begins a 20-year correspondence, interrupted by a stay in an asylum and a few misunderstandings. Mary falls in love with a neighbor, saves...