Mother Marie-Thérèse is the surviving victim of one of Belgium’s most notorious crimes, involving kidnap, rape, prolonged torture, and finally murder—all of which took place in enchanting, picturesque Bruges, Venice of the North. Her co-victim, an American priest, Father Thomas Jensen, did not survive. Although his remains were never found, Piet Van Kampen confessed to killing the priest, for which he received a sentence of life without parole.
Twenty years later, on the day after the convicted killer's death, Célèste De Smet, a journalist for LeSoir.be, draws a career-making assignment, an exclusive interview with the nun. Reeling from the day-old breakup of a long-term relationship, Célèste arrives at the motherhouse of the Servant Sisters of Jesus and Mary in Florenville, a town in Southeastern Belgium. She expects to spend a single afternoon with the nun and be on her way back to the capital. Mother Marie-Therese (Tesse) has a different plan. She bargains with Celeste for an exchange of life experiences, Célèste’s for hers—in that order. Taken aback by this unexpected request and a possible delay in her return to Brussels, Célèste weighs her options. She chooses the interview's career potential over her reluctance to open her life to this stranger.
Thus begins a cycle of deeply personal revelations that will occupy the two women for several days. Célèste outlines her youth and upbringing, including a secret vow made to God and broken. In return, Tesse responds to the reporter’s opening query, how she and Fr. Jensen happened to be in Bruges together on the day of the kidnapping. Tesse then gets Célèste to discuss an unresolved adolescent trauma. The reporter has carried the guilt and shame of being responsible for her missionary priest-uncle's leaving the active ministry and marrying an African woman who was pregnant with his child. Célèste has never spoken of the triggering incidents that occurred when the priest was visiting the family. In return, Tesse relates details of her and Tom’s captivity, including repeated druggings and sexual abuse.
Sensing that Célèste had yet another secret to tell, Tesse coaxes her to share the matter of her broken vow, using as bait the promise that she still has one final piece to her own story to tell. Unable to resist being privy to the conclusion of the Tesse and Tom story, Célèste agrees. But she is unprepared for the shock of Tesse’s final revelation. Having received the information, the young reporter fears that curiosity might have involved her in an ongoing crime that could cause her to lose everything.