AMONG THE TEN THOUSAND THINGS, by Julia Pierpont. Random House, 322 pp., $26.
Jack Shanley is hardly the first middle-aged family man to seduce a pretty young thing he meets at a party. And Deb Shanley is hardly the first wife to find out. But Deb may be the first injured spouse to be informed of the extent of the sexual dalliance by her kids.
Julia Pierpont's first novel, "Among the Ten Thousand Things," opens with a Pandora's box of printed emails sent to Deb by the dumped mistress. Eleven-year-old Kay opens the box first, thinking it is her birthday present. Instead, she gets a flurry of lascivious messages so disturbing that she shares them with her 15-year-old brother, Simon. The duo then pass the box on to their mother, who already knew about the affair but is appalled anew when confronted by its randy nature.
"Ninety-two percent of Americans disapprove of extramarital affairs," Pierpont writes. "Deb had done some research, online. Sixty-four percent would not forgive an unfaithful spouse, and sixty-two percent would divorce one. The site did not explain the other two percent, who neither forgave nor divorced. Catholics or possibly black widows." And Deb, it turns out, at least for a while. The novel chronicles the uneasy period during which this prosperous Manhattan couple decide how to move on with their lives and deal with their children's confusion -- Jack crashing on the couch, or at his artist's studio, depending on the fluctuations of Deb's fury.
Fifty-five-year-old Jack has enjoyed a successful career as an avant-garde artist until one of his installations explodes, threatening him and his gallery owner with lawsuits. Deb, 41, has abandoned her ballet career for motherhood; now she teaches dance, as her former colleagues bask in their status as divas. Much of "Among the Ten Thousand Things" concerns the tricky balance of artistic ambition and family life. Jack, who is cavalier about his sin -- "It's not like I killed anybody" -- sleeps with other women partly to fuel his art. Deb, on the other hand, never felt as confident about dance. "The best a dancer can do is bring life to another person's steps. Jack didn't have steps to follow. He made his own."
Like a good family therapist, Pierpont gives equal airtime to all members of the Shanley family. Simon, a typical teenager, is able to distract himself from the travails by smoking pot, playing video games and thinking about girls. Kay misses her father intensely and also finds herself unmoored by all of the talk of sexuality that she is too young to understand. In her spare time, she writes scripts for some quite funny, X-rated "Seinfeld" episodes.
In the middle of the novel, Pierpont provocatively reveals how all of the Shanleys' lives will turn out -- then returns to the period she is covering. Her argument is that the dailiness -- the "ten thousand things" of small impressions and observations, shifts in mood -- defines a life, not the plot or wide arcs.
Of course, this argument depends on how well the novelist captures the poetry of the mundane. Pierpont sometimes misses in this regard. There are detailed descriptions of a few too many meals -- Chinese, pizza, turkey provolone subs -- and some details that the reader could do without: "In the kitchen the stove clicked on. Rice slid in all its pieces from a cardboard box. The printer was running in the back bedroom, and she could hear the cheerful chimes of text messages arriving."
In general, though, Pierpont's voice is wry and confident, and she is a fine anthropologist of New York life, especially for those creative types who never quite manage to fit in with cultural expectations.