Santa Fe's tenacious, even-tempered p.i. Joshua Croft is hired by VIP Norman Montoya to find Melissa Alonzo and her small daughter Wynona. Melissa, ex-wife of Montoya's movie-star nephew Roy, has disappeared in the wake of a nasty custody case in which she'd accused Roy of child abuse. The judge's decision to grant her ex- husband unsupervised visiting rights has sent Melissa into a protective network called Underground Railroad. Croft must also explore her connections to Sanctuary, a group fighting repression in Salvador. Melissa had recently made an unexpectedly short visit there and may have become the quarry of a less benign searcher--a theory lent weight by the murder of her sister Cathryn. It all ends in a tense confrontation joined by Croft's computer-whiz partner Rita Mondragon, newly freed from her wheelchair (At Ease With the Dead, 1990, etc.). The author probes a currently trendy subject with sensitivity; vivid characters; suspenseful plotting; and some surprises reserved for the windup--in another satisfying Joshua Croft adventure.