This is not your average nun.

The Catholic church is no stranger to music, but when 25-year-old Sister Cristina Scuccia appeared on The Voice of Italy, she floored the audience and judges with her performance.

The nun performed a stellar rendition of "No One" by Alicia Keys in full traditional attire while three of her fellow nuns watched backstage. But nothing about her performance was conventional.

The judges' backs are turned to the performer, and they are only allowed to turn face-forward if they want that singer to join their team. One by one, the judges are awed by Scuccia's performance — and even better are the looks on their faces when they discover who is singing.