IT'S A MOMENT JILL RAPPAPORT WILL never forget: introducing her pals Christie Brinkley and Peter Cook. "I said, 'Peter, do you know Christie?' " recalls Rappaport, NBC's Today entertainment correspondent, of the Feb. 25 meeting of the supermodel, 42, and the architect, 37, at Rappaport's Water Mill, N.Y., home. "He turned around. She turned around. I just remember those two sets of piercing blue eyes." So does Brinkley's pal, art dealer Mindy Moak, who also witnessed the historic lens lock. "I sensed the chemistry immediately," she says. "I knew to get the hell out of the house. I grabbed Jill and said, 'Let's go.' "

It may have been spontaneous combustion, but it wasn't the first time they had met. Both recall an encounter at a Studio 54 bash in 1981 and crossing paths over the years at parties. But, says Brinkley, "I was always married. I never paid attention." On their first date, in early March, the couple went to dinner at the trendy Easthampton eatery Nick & Toni's and to a movie. "After the date, Christie called me," says Rappaport. "She told me there was never a lull in the conversation and they had such a great time." And still do: On Aug. 3, Cook presented Brinkley with a sapphire and diamond ring. "We don't know when we're getting married," she says. "We're just happily engaged. We're toying with dates. I'm extremely happy."

It's a welcome change of pace for the Uptown Girl, who had been living in a downcast world since the dissolution last December of her 11-month marriage to developer Ricky Taubman. This divorce, her third (Brinkley's 1974 union to French illustrator Jean-Francois Allaux ended after seven years; in 1994, she and pop star Billy Joel split after nine years), was also the most acrimonious. She and Taubman had met in March 1994; a few weeks later the helicopter in which they were flying on a ski vacation crashed into a Colorado mountain. The drama of the accident brought them closer together, fast. "The crash obviously had a major impact on us," Taubman, who suffered a punctured lung and broken bones, said at the time. (Brinkley sustained bruises and a sprained wrist.) By the time they married in December 1994, she was pregnant with their son.

But the birth of Jack Paris last June did little to bolster the already flagging union. Amid accusations that she prevented him from seeing Jack (Taubman "canceled visitation every time it was offered," Brinkley's lawyer Eleanor Alter said at the time) and charges that he hadn't repaid $1.5 million she had loaned him ("There is no debt," his lawyer Jay Levely told New York's Daily News), the couple broke up. In December, Brinkley was granted sole custody of their son.

Supported emotionally by friends and family, Brinkley was determined to make a new life for herself and her children (her daughter with Joel, Alexa Ray, is 9). "Christie wasn't looking to meet anybody," says Moak. But in Cook, she seems to have found someone who shares her priorities. "He loves kids," Moak continues. "It's genuine, because he has lots of nieces and nephews." The fourth of six children of Harry, 76, an Exxon engineer, and Jean, 72, a homemaker, Cook grew up in West Orange, N.J. After graduating from Rensselaer Polytechnic Institute in Troy, N.Y., in 1982 with a degree in architecture, he modeled briefly, appearing on the cover of GQ in 1981. But, says ex-model and close friend Richard Wiese, Cook never took the smile-and-pose job seriously: "He liked to go to parties and meet girls." By 1983, Cook had abandoned the cameras and begun a successful business designing houses.

These days, though, the home that Cook is most preoccupied with is the rented Long Island, N.Y., estate where Brinkley and brood live. "He intends to raise Jack as his son," says Wiese, "and I wouldn't be surprised if they have kids." Cook's mom thinks the engagement is a fine idea. "We're delighted," she says. So are Christie's friends. "The only problem I see," says Moak, "is for the people who look at them. You could get a retina burn. You definitely need sunblock."

PETER CARLIN
MARIA EFTIMIADES in the Hamptons and LIZ McNEIL in New York City

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