To the author's credit, this would-be twisted tale is remarkably readable, even though Allen (Leftover Dreams, 1992, etc.) runs out of ideas well before her final chapter. New York City photographer Snow Devane lives an empty life of meaningless sex with a string of married men, and even her relationship with her mother, Anne, seems strained, oddly out-of-kilter. Not until Anne suffers a heart attack does Snow fully understand the emotional tug-of-war she's had with the woman who raised her: At her death, the older woman reveals that she isn't in fact Snow's biological mother; and she's taken the time to write Snow a letter explaining how she snatched her as a child, then acquired a false identity for both of them. The strain on a reader's credibility so far (Allen provides color-by-numbers information on finding one's birth-parents) is increased by the fact that Anne has left Snow gobs of cash, stock and other holdings worth well over a million. When Snow and sidekick Katie set out to find Anne's real identity, they run into all kinds of roadblocks, but none too tough to hurdle. It's in these middle sections that the story manages to come alive with a bit of suspense and mystery. Where did Anne get all that loot? What's inside the safe-deposit box? Who is Snow? There will be money, yet again, in the answer to that last question, though Allen, failing to wrap up the mystery of Anne's yet-earlier life, fudges a disappointingly large swath of her ending. Badly unsatisfying, then, but so goes escapism, attendant upon its flaws: On the summer's beaches, readers will willingly close their eyes and follow Snow to her reward.