Convent orphan Michael Antonio idolizes his uncle, renowned magician and juggler Marko the Magnificient. Marko is coming to San Tanco to visit Michael, an opportunity Sister Bertrille cannot let pass. Since the hot water pipes in the convent had just burst, she persuades the Reverend Mother to hold a benefit concert headlining Marko the Magnificent, with some other peripheral acts, including a trio of singing nuns (Sisters Bertrille, Jacqueline and Ana). The Reverend Mother thinks it's a good idea since she has seen the amazing feats of Marko. Marko however does not want to do it since he has come to San Tanco for some rest and personal time with Michael. Feeling pressured from Michael as well as some pre-publicity of the concert, Marko reluctantly concedes to doing it. Another reluctant performer is Sister Ana, who has stage fright. Back to Marko, Sister Bertrille learns that Marko's reluctance masks the fact that his hands are afflicted with arthritis and he can no longer perform magic or juggle. Ultimately Sister Bertrille can do nothing to overcome Sister Ana's stage fright - the Reverend Mother goes on in her place - but Sister Bertrille comes up with a solution for Marko. They can create a magic act around levitating Sister Bertrille, who will be flying on her own. The concert ends up being a hit, even according to the entertainment bible, Variety magazine.
—Huggo