By Alexander McCall Smith (Pantheon Books, 257 pages, $24.95)

For fans, reading the No. 1 Ladies' Detective Agency books is like visiting old friends. But when the themes are the same, even old friends can become a bit boring. That's how I felt about the last few books in the series, so I was surprised to find new depths in the 13th book. Our hero, Mma Ramotswe, has always been kind and sensible, but her musings on power, mortality and human frailty and foolishness seem more perceptive here. Grace Makutsi's beloved shoes still talk to her, but she is wrestling with guilt at her newfound status as the wife of a prosperous man. And, as a bonus, the legendary American Clovis Andersen, author of "The Principles of Private Detection," makes an appearance as a sad Midwesterner who is dumbfounded at his elevated standing with Mma Ramotswe and Grace. But he turns out to be an able ally as the trio fights various injustices. As usual, the "mysteries" are quickly and easily cleaned up, but the gentle and telling portrait of the human condition lingers for this reader.



Buried in the Sky

By Peter Zuckerman and Amanda Padoan (W.W. Norton & Co., 285 pages, $26.95)

Climbing the world's highest peaks used to be reserved for an elite group of superclimbers, but with the widespread use of oxygen and Sherpa guides, more people are finding the ascents within reach, albeit at a high cost -- tens of thousands of dollars, and sometimes their lives. This rush of climbers has only increased the danger. In May, four people died on Everest, a toll blamed primarily on a "traffic jam" on the icy slopes. Stories of extreme mountain ascents aren't uncommon (notably Jon Krakauer's bestselling "Into Thin Air"), but "Buried in the Sky" takes a different approach, examining the story of a deadly ascent of K2 from the perspective of two Sherpa guides, Chhiring Dorje Sherpa and Pasang Lama.

The role of high-altitude guides is difficult, and not only because of the conditions. Guides are entrusted with the lives of rich, sometimes inexperienced climbers and can be expected to give up their oxygen, their gear and their lives to help their employers "summit."

So when disaster strikes in the K2 "death zone" (where thin oxygen and perilous conditions affect judgment and the body's ability to live) and Chhiring finds Pasang stranded on an ice wall, without an axe and waiting to die, he makes an uncommonly human choice, risking his own life when the custom of the mountain says you're allowed to save yourself. Although Everest is the tallest mountain on earth, K2, "the Savage Mountain," is a more difficult -- and deadly -- peak, and this compelling story brought back from its slopes is a worthy tale about a little-known aspect of these high-stakes climbs.