Messages-from-space yarn from the versatile author of Illegal Aliens (1997), etc. By 2017, messages from Alpha Centauri A have been arriving at Earth for ten years, but only the first few have been deciphered. Univ. of Toronto psychologist and message decipherer Heather Davis is separated from husband Kyle Graves, a leading quantum computer researcher; but then their daughter Becky accuses Kyle of abusing her. At first incredulous, Heather soon entertains horrid doubts. Poor Kyle, meanwhile, knows he's innocent--but, agonizingly, wonders whether he's repressing memories of abusing Becky (their other daughter, Mary, inexplicably committed suicide). Then the messages from space stop. Even though Kyle's attempt to demonstrate a working quantum computer fails, two mysterious groups--one offering megabucks and another message to decode, the other also offering megabucks while making veiled threats--want his work suppressed. He rejects both. Heather realizes that the Centanran messages, correctly arranged, form an unfolded four-dimensional hypercube. She builds a model that incorporates the substances specified in the previously decoded messages, climbs inside--and the thing folds her up into the fourth dimension! Not only that, but she's able to plug into humanity's collective unconscious, or overmind. Kyle, she learns, is indeed innocent, and Becky's the victim of an overzealous and suggestive therapist. Moreover, the Centaurans have sent a ship to make contact. Best of all, humanity's overmind meets the Centauran overmind with astonishing consequences. An intelligent and absorbing double-stranded narrative, generally well paced, accelerates to hyperspeed in the last few pages.