Margaret, a young novice, travels to Rome with the expectation of finalizing her vows, receiving a warm reception from Cardinal Lawrence. She’s given a tour of what will be her new residence and quickly meets Carlita, a quiet woman who prefers spending time alone drawing. Margaret finds herself drawn to Carlita, but even more so by events unfolding within the hospital's maternity ward. A disturbing story shared by Father Brennan sends Margaret reeling, initiating an investigation that uncovers a vast conspiracy—one devised by the church to ensure its survival, yet capable of destroying it and everything else. The film moves along at a reasonable speed for parts of its runtime, featuring occasional unsettling imagery (it’s peculiar how medical instruments can resemble torture devices). However, knowing the ending since 1976 diminishes any real feeling of danger, and the few attempts at startling moments are easily anticipated. Nell Tiger Free makes an effort to bring some life to her role, performing adequately, but Bill Nighy feels underwhelming, and Charles Dance’s brief appearance is ultimately pointless within these disappointing events. Prequels present a challenge, and this one struggles; it seems we've encountered this plot before, leading me to believe the nun-centered narrative may be exhausting itself. It felt like a short story that was expanded beyond its natural length.

Source on TMDB