There's a wonderfully elegant and provocative story lurking within Kundera's latest, but it's not that easily accessible. In a metafictional conceit that works, Kundera, at his health club in Paris, sees an aging woman make a graceful but casual gesture of farewell to her swimming instructor. The gesture is seminal for Kundera, who begins to create a part-fictional/part- real existence for this woman whom he calls Agnes. Agnes, still mourning the death of her beloved father, yearns for solitude--for a life alone in the mountains of Switzerland away from, but in contact with, husband Paul an daughter Brigitte. Agnes also has a younger sister, Laura, who, Agnes feels, follows too closely behind her--''She imitated, but at the same time she corrected.'' Laura, who perfectly identifies with her body (unlike Agnes), who sees her body ``as an old factory scheduled for demolition,'' has many affairs--including a torrid one with Bernard, a famous media personality, increasingly uncertain of his worth. As he relates Agnes's story, Kundera also meets with some of the characters involved and--in separate chapters in which he introduces literary greats like Goethe--explores the meaning of immortality, love, fame, and the contemporary preference for images (themes that preoccupy his fictional characters as well). The affair with Bernard ends, Laura is devastated, and Agnes retreats to Switzerland. Driving back, she is killed in a bizarre accident, and Laura, who had long yearned for brother-in-law Paul, finally catches up with her sister by marrying him. And Kundera, again at his club, now sees Paul perform ``that clumsy male imitation of a beautiful female gesture'' and disappear. Agnes and her gesture have inspired a remarkably tender and wise story about love and death, but the novelist Kundera, gifted and original, might consider a separation from the philosopher Kundera, an often banal and intrusive heavy.