BOOK REVIEW : A Lighthearted Look at Three Post-College Lives : SOMETHING BLUE <i> by Ann Hood</i> . Bantam, $18.95, 272 pages

Three women: Lucy is the stable one, with a burgeoning artistic career and a devoted beau. Julia is the wild one, with spiked hair and a penchant for foreign men. Katherine has always been the most conventional of the trio, destined to marry her childhood sweetheart and relive her mother’s life.

“Something Blue” is saved by a refreshing reluctance on author Ann Hood’s part to take the problems of her three heroines too seriously. She manages a brisk, witty new take on the standard theme of college ex-roommates on their own in New York.

The novel loses no time in departing from the formula. To support herself while editors dawdle over her fanciful illustrations, Lucy works as a guide for Whirlwind Weekends, a tour company specializing in four-day European trips. She has the ideal mate in Jasper, who believes that roast turkey cures jet lag, and always has one waiting for her when she returns. Jasper is a dancer, though he’s obliged to support himself as a bartender between shows.

Julia also has theatrical ambitions, though hers aren’t so lofty. When we’re introduced to her, she’s auditioning for a bit part in a slasher film, got up for the role in black leather, white lipstick, and a rose tattoo on her arm.

Julia likes the tryouts. Actually getting the roles doesn’t matter, because she’s found a way to live in New York rent-free. She’s a house-sitter, and far more reliable than she looks. Though she’s actually from Brooklyn, she has reinvented herself as a Milanese, an identity she finds more romantic.

Katherine makes her appearance on the Amtrak Minuteman, heading for Penn Station at 7:05 a.m. on her wedding day, having abruptly decided to leave her fiance, her wedding gifts and her bridesmaids in Connecticut. She’s planning to stay with Lucy, expecting to find the excitement that will forever elude her if she marries Andy and becomes a doctor’s wife. In every other respect Katherine is her old self, still committed to her preppy image, convinced that a batch of brownies is the answer to life’s major crises.

In the ensuing year, Lucy is able to cut down on the Whirlwind Tours as her talent for illustrating children’s books is increasingly appreciated. As her career waxes, Jasper’s wanes, a contrast exacerbated by her publisher’s obvious romantic interest. Jasper is sweetly adoring, but Nathaniel Jones is masterful--a trait not much in evidence among the sensitive new men of the decade. Despite misgivings, Lucy finds herself responding to Nathaniel’s attentions. Less jet lag and more illustrating assignments mean a reduced need for massages and stuffed turkey. Success requires longer business lunches and frequent trips to the home office in Boston.

Julia, after a series of hectic love affairs with representatives of underdeveloped countries and frequent moves from one uninhabited apartment to another, becomes attached to one lover and one locale, both exotic enough to satisfy her.

On, the name of the significant other, is a Chinese percussionist. The loft she’s presently guarding is so starkly under-furnished that she finds herself breaking all self-imposed rules against acquiring possessions. By the end of the novel, Julia has admitted she’s not Italian and buys a food processor.

Katherine does her best to be a contemporary New York woman, dating men she meets in markets and bank lines, and even enjoying a romance with a chubby Elvis Presley freak. But when her abandoned fiance shows signs of recovering from her defection, she reconsiders. Never solemn, “Something Blue” is crisp contemporary fun, putting the dilemmas of the thirty-something generation into proper perspective. They’re genuine enough, provided that you take Hood’s lighthearted long view.

Next: Carolyn See reviews “A Change of Luck” by Julia Markus (Viking).