Here’s what’s new in bookstores this week:• Hunting Shadows by Charles Todd (William Morrow, $25.99) — The bestselling mother-and-son writing team of Caroline Todd and Charles Todd is back for the 16th novel in the Inspector Ian Rutledge series, set in post-World War I England. In this one, the Scotland Yard inspector is investigating the fatal shootings of two men in the Fens outside London.