Even detectives can get conned. Teddy Xanakis pulls a pretty good one on Kinsey Millhone early in X, and on top of it Teddy paid her with counterfeit $100 bills. Following the events of W Is for Wasted, Kinsey is in a position to investigate a personal case without much hope of being paid, so she works the case to a generally satisfying end.
Teddy's con isn't the main plot, though. X is mostly a direct sequel to W Is for Wasted, with Kinsey diving into a cold case left behind by Pete Wolinsky. Pete's ethics were questionable at best, but Kinsey became friendly with his widow Ruth while solving Pete's last case (a case in which he claimed to be working with Kinsey), and ultimately his murder. The IRS (or someone claiming to be from the IRS) claims that there's a problem with Pete's estate, so Ruth asks Kinsey to search the box of Pete's documents (marked with a large X) which Kinsey has under her desk.
Pete's files turn out to be from the case that ended the partnership between Benjamin Byrd and Morley Shine, the investigators under whom Kinsey apprenticed and with whom Pete occasionally worked. Ned Lowe's wife apparently committed suicide and Pete's investigation cast doubt on the verdict. Since she has no other active cases (and a financial cushion thanks to her inheritance), Kinsey picks up the cold case, solves it, and partially rehabilitates her colleague's reputation.
There are only two more books to come in the Kinsey Millhone series, and I'm going to miss them. The last few have been among the best, and X didn't disappoint me. Beside two strong mysteries, Grafton included a comic subplot involving Henry Pitts's interest in water-saving technology and his and Kinsey's strange new neighbors. She's also bringing back characters from Kinsey's past. Two of Kinsey's ex-lovers, Cheney Phillips and Robert Deitz, appeared in W is for Wasted, and Phillips plays a major part in X as well. There's also a cameo by Kinsey's other ex, Jonah Robb, and a visit to her old friend Vera (now the mother of three kids under five and 8 months pregnant with twins). With Kinsey's recent discovery of Millhone relatives and trust with her maternal-side family, it looks like Grafton is setting up a happy ending for her heroine. I just hope it includes Henry Pitts.