A devoted scientist and family woman finds her life suddenly jumping off the rails after making a shocking discovery about her sister's disheveled apartment. Anges is a woman who thrives on order: Her career is going well, her marriage to husband Walter is a happy one, and her relationship with adoring daughter Leni is a picture of motherly love. Though her career and personal life don't leave her as much time to spend with sister Karola as she would like, the pair get along like old friends and rarely quarrel. One day, Karola announces that she is going away for a while, and requests that Agnes water her plants in her absence. Upon visiting the apartment, Agnes observes that it appeared to be abandoned in haste. Gradually, Agnes begins to feel mysteriously drawn to the apartment, visiting on a regular basis and eventually assuming an air of ownership over the place. Upon discovering that the apartment in fact belongs to a married couple, Agnes begins to investigate. Apparently, the wife had died on her way to a rendezvous with her lover, and in his grief husband Bruno had simply abandoned the flat and moved on with his life. After falling asleep in the apartment one day, Agnes awakens to the touch of a man lying in bed beside her. It's Bruno. While the two nary exchange a glance, much less their names, they instinctively make love. But things start to change for Agnes once she begins to visit Bruno on a regular basis, and she begins to feel as if she is simply drifting as Bruno struggles to repress his grief. Her home life falling apart in the wake of her secret affair, Agnes begins to live with Bruno like normal lovers despite the fact that both release the ultimate futility of their clandestine relationship.