WHEN LAST SPOTTED IN PUBLIC together, Mira Sorvino and Quentin Tarantino were the picture of unconnubial bliss: lip-locked over champagne, truffle soup, caviar and lobster risotto at the posh Manhattan restaurant Two Two Two on Valentine's Day. "They were kissing, hugging and romancing," remembers the maitre d'. "It seemed like they were very much in love."

Emphasis on the were. A somber Sorvino emerged March 6 from her trailer on the set of At First Sight, a fact-based drama being filmed in Manhattan, to walk her blonde mutt—alone. The actress, 30, said that although she and the director, 34, "still love each other very much," they had reached a "mutual" decision: "At this point in our lives, we should not be together." She declined to elaborate, but her publicist Mara Buxbaum quashed rumors that Val Kilmer, Sorvino's First Sight costar, played any role in the split. "She is not involved with anyone," Buxbaum says.

Nor, apparently, is Tarantino, which makes the breakup as hard to figure as the romance that preceded it. From its liftoff at the Toronto film festival in September of 1995, theirs was a bicoastal attraction of opposites—she, the daughter of actor Paul Sorvino and a magna cum laude Harvard grad; he, a ninth grade dropout who clerked at a Manhattan Beach, Calif., video store before hitting it big with Reservoir Dogs and Pulp Fiction. They never lived together—when Sorvino left New York to star in The Replacement Killers a year ago, she leased a house in L.A. instead of crashing at Tarantino's. Yet they did rendezvous frequently and often talked about working together. "I'm tired of all these guys directing her," Tarantino told US magazine. "It's my turn."

If he has lost his turn, he seems to be taking it in stride. Now starring in his first stage role, a Broadway-bound production of Wait Until Dark, Tarantino I was all smiles at the March 5 cast party in Boston. When actress Joycelyne Lew told him she was solo in town that weekend, Tarantino had a ready reply. "He was being friendly," reports Lew, "and said he was alone too."