Francis Clemens--Frank--is having an affair with Josephine Felielle--Billy. Both of them are married to other people. They're both involved with economics professionally, they Jive in New York, they are attached to their spouses by both conviction and honor, and these spouses are often away. So much for similarities. Otherwise, Frank is a sensualist about clothes and food, Billy a slob whose shoes are taped together and who has nothing in her refrigerator. She's laconic and unsentimental; he's the more unbuttoned of the two. They are, in fact, a sort of Odd Couple--wherein is found a good deal of the charm in these five connected if not quite connecting stories by the ever-interesting Colwin (Happy All The Time, Family Happiness). Until Billy calls a conscience-driven halt to the liaison, they both are happy (""as happy as it is possible to be under those circumstances, which bring the kind of happiness that is devoid of any contentment""). Yet, as Colwin's shading warns early on (and readers may notice that Frank is always the narrator of the morally dubious stories, Billy of the post-sin ones: a sort of stacking of the deck): ""It is one of the sobering realizations of adult life that love is often not a propellant. . . It often seems that the function of romance is to give people something romantic to think about."" The stories mean to be anti-romantic, in fact; there's far more snacking that goes on than lovemaking; and at one point, Billy's reactions to her own adultery are balanced-out at ""sorrow, guilt, glee, humor, anticipation."" The problem is that you don't believe an awful lot of it. Francis comes off as too unconscious, almost brutally level, plumb-lined; while Billy seems to be less a lover than a treader of water, going through the motions of infatuation until she can make for the open sea and have the secure-marriage-with-baby that she's destined for (and does get, post-Frank). Partially this is the overlap's fault--the segments don't seem quite well-aligned enough--but there's also a touch of smugness here that seeps out at the edges of cool delight to Colwin's always truly impressive comic-prose style. Frank seems a strawman set up to then be knocked down; and both Frank and Billy seem to be going through what's finally only a self-restricting acrobatic trick, one of some difficulty but without the sweat. Family Happiness showed Colwin able to approach a Russian-like miscellany of a-directional feeling--and while no one would expect her to duplicate Anna Karenina, it is somewhat surprising to find so little dirt under her anthorial nails when dealing with a subject this compromised and unstable. Crystalline (and enjoyable for it) but ultimately inexpressive work by one of the most intriguing American fiction writers--here coasting.