Alice Loudon seems to have everything: close friends, a loving boyfriend, a successful career. Then one day she meets a stranger while crossing the street and - impulsively, immediately - abandons her old, safe life for a passionate affair. It leads her into a dark, dangerous realm of eroticism and extreme experience that both entices and alarms her.

Adam Tallis, heroic survivor of a disastrous mountaineering expedition, teaches her things about herself she never knew. As she learns more about her lover, she enters his world of risk and transgression - and begins to uncover a past filled with troubling secrets. But love and sexual obsession overwhelm her until they threaten everything: her safety, her sanity, and, finally, her life.