This flamboyantly anti-realistic novel is more symphonic prose poem than narrative. It is a paean to love, idealized, and also a love letter to New York City in all its rhythms, human and natural, its moods, weathers, changing colors of sky and water. The writing is so highly lyrical and lovely that sometimes my aesthetic receptors clogged with a surfeit of beautiful language. It took me a while to appreciate the book's charms, almost 300 pages before I succumbed to its idiosyncratic spell. Mark Helprin's "In Sunlight and in Shadow" (Houghton Mifflin Harcourt, 705 pages, $28) is not for you if you expect plot and realistic dialogue and the usual flawed characters of modern fiction.

The story, such as it is, is set in 1947. Harry Copeland, 31, who is still reliving his terrible war years as a paratrooper, meets 24-year-old Catherine Hale, heiress and talented singer/actress, on the Staten Island ferry. They fall instantly and irrevocably in love, with emotions so incandescent and yet deep that they will not flag for more than 700 pages. These are no ordinary protagonists but beings of rare loveliness in both looks and character. Their conversations, monologues and thoughts more resemble high rhetorical disquisitions on love, time and the tension both lovers are ever aware of between the fragility and evanescence of the moment and love's ability to hold and transcend it. (Some of the lovers' analyses of life do become somewhat gassy; Helprin is not afraid of grand gestures.)

The postwar years are fresh, almost magical to Harry in their peaceful rhythms of nature and culture restored to a kind of harmony.

Catherine feels daily magic in her own way, when she steps onto the stage and transforms life into art with only a few steps, an intake of breath and the launching of a song.

The one main subplot, aside from the celebration of love, is a rather vulgar one, involving a Mafia shakedown of the leather goods business Harry has inherited, and his resolve to take action with the help of former paratrooper buddies. In the climax, as well as Harry's war flashbacks, Helprin shows he can write potent and thrilling action scenes, but they mesh awkwardly with the dominant lyrical tone.

There is a tragic climax, perhaps inevitably, since it is difficult to imagine a perfect love enduring unchanged by time.

But the novel's main theme is the loving embrace of the small visions and actions that become extraordinary if we have the spirit and energy to notice their textures. Here is Catherine, walking in the city. "She wandered, overwhelmed by images -- by thousands of faces, each telling of deep or despairing lives; by clouds garlanding the great buildings; by the engines of the city's commerce; the wind lifting briefly the hem of a woman's cream-colored coat as she glided south at the edge of Madison Square; the sun in blinding flashes upon a hundred thousand windows; bridges sailing high above blue waters and whitecaps; pigeons rising in almost exact synchrony from sidewalks darkened by rain, banking in a mathematically perfect curve, wings still, their perfection the gift of the omnipresent and invisible air."

Brigitte Frase is a freelance critic in Minneapolis.