STRANGERS By Rosie Thomas Simon and Schuster. 321pp. $17.9

Romance isn't what it used to be. No more meetings at tea dances or even on the jogging trail. These lovers of the '80s -- Annie and Steve -- meet under the rubble of a London department store bombed by terrorists when both were doing last-minute Christmas shopping.

It may sound a little too trendy for comfort but the opening chapters of "Strangers" are a tour de force in more ways than one. The panic, uncertainty and claustrophobia of these two trapped survivors is mesmerizing: "It was as if her body were clay that had been crumpled up and crudely remodeled, stopping short at the knees." And before the dust from the explosion has settled you have fallen into the clutches of Rosie Thomas, a gifted British writer who dissected the life of a Welsh village in her first novel, "The White Dove."

The balance of her new novel, divided between hospital and home, delicately probes how Annie deals with being a wife, a lover and a mother. She lies under a metal fire door with multiple injuries, married to Martin; she is trapped in the terrifying darkness and pain with her future lover Steve, a divorced, cynical advertising executive on his way to the top; she is also the devoted mother of two small boys, Ben and Tom.

It goes without saying that nearly losing one's life in company with someone else forms a bond unlike any other, but Annie has been married happily, quietly, securely to Martin for 11 years. "I chose what would be safe and simple. Because it would be wholesome," she tells Steve in the darkness. "That's a funny notion isn't it? As if you can turn your life into wholemeal bread."

Steve is divorced from a model he married because he was "amused at the prospect of having a wife." As they wait for the heat sensors and the demolition crews to find them, Annie and Steve talk without restraint, their hands touching, never having seen each other's faces.

Annie's relationships with both Steve and Martin (who waits behind the police lines in dreadful uncertainty) are confused and believable. Both men have faults and strengths -- the kind that are only too easy to identify with. The result is that Thomas ends up somewhat entrapped by her own skill. Obviously, if a sympathetic heroine is torn between two interesting and lovable men, no neat symmetric conclusion to the tale can be reached. Martin offers Annie familiarity, a home, a life she is used to and the happiness of her two children. Steve offers glamor, ease (he drives a BMW and frequents quietly elegant restaurants), sensitivity, passion and a new dimension to her previously cocoonlike domestic existence.

A middle-aged housewife trying to choose between her husband and her lover isn't the most novel plot, although I did read the whole book in one sitting to find out who ended up where. Annie does swing between Martin and Steve perhaps once too often. The cynic might be tempted to mutter, "Make up your mind!" But Annie has a strong enough hold on our sympathy and respect by the time the rescuers reach her to carry us along.

Catching the ordinary while avoiding the banal is Thomas' strength. One of the challenges of Annie's story is to portray the bond between Annie and her sons without plunging into sentimentality or cliche'. Maternal love is an emotion that doesn't translate easily into words, but Annie's day at the fun fair with Ben and Tom has a sticky beauty about it:

" 'What do we go on, Mum?'

"She took one hand in each of hers and swung them round."

" 'Everything.'

" ... Within the circle of the fair Annie felt suddenly no older than Thomas and Ben. The fierce pleasure of childhood excitement touched her, and it was intensified by the added, subtle pleasure of her adult capacity to indulge her children, and share their indulgence."

Mother and children play "William Tell" on the heartstrings at a brisk tempo, but Thomas succeeds in avoiding the manipulative or the trite by a hairsbreadth.

Rosie Thomas is the kind of storyteller whose characters shop in the neighborhood store, yet there is nothing tired or boring about them -- a much greater achievement than it sounds. "Strangers" is straightforward, well-crafted popular fiction, offering insight into the lives of others and a brief escape from our own. The reviewer is the editor of The Washington Post Book World.