BookMark: U is for Undertow by Sue Grafton By VANESSA MCLAUGHLIN • June 23, 2010 Related Program: WPSU's BookMark Tweet Share Google+ Email Add a little mystery to your summer. In the most recent book in the alphabet mystery series, Grafton sends Kinsey Millhone looking for a kidnapper. Visit the author's website. Read an interview with the author in TIME magazine. Here's another review of U is for Undertow.