In her latest novel, Susan Richards Shreve chronicles the arcs described by two lives bound for collision as their owners carom around the capital. Familiar and strange as the sounds and shades of a Metro car at rush hour, The Train Home is a book with a D.C. mise en scène but happily devoid of pompous Washingtoneity. Shreve reads from Train at 5 p.m. at Politics & Prose, 5015 Connecticut Ave. NW. FREE. (202) 364-1919. (Michael Dolan)