It’s Christmas Eve in 1977 Philadelphia, and DELORIS is in the middle of a high-energy audition with her backup singers (Take Me to Heaven – Nightclub). She and the girls are performing for CURTIS, Deloris’s boyfriend, and his thugs, JOEY, TJ, PABLO, and ERNIE. Despite praise from the thugs, Curtis doesn’t believe Deloris and her singers are ready to perform in his club. After his rejection and a disappointing Christmas gift, Deloris decides that she deserves better, walking away from Curtis and his club with confidence (Fabulous, Baby!). However, Deloris is unwillingly drawn back in when she accidentally witnesses Curtis murdering Ernie for being a police informant. Curtis confronts her, but she flees. 

Deloris goes straight to the police station where OFFICER EDDIE SOUTHER takes an interest in what she has to say. Immediately recognizing the officer as “Sweaty Eddie,” a boy who had a crush on her in high school, Deloris puts her faith in Eddie, trusting him to find her a place to hide from her dangerous boyfriend. Eddie thinks of “the perfect place,” Queen of Angels Cathedral in South Philadelphia. MOTHER SUPERIOR hesitates to take in the “wayward woman” MONSIGNOR O’HARA describes, but upon his insistence, she agrees. Both Deloris and Mother Superior are shocked when they discover Deloris will be hiding there for a month. Mother Superior is especially distressed to discover that Deloris is not religious. She describes Deloris’s new environment to her, handing her a nun’s habit to wear (Here Within These Walls). 

Mother Superior introduces Deloris to the nuns, referring to her as SISTER MARY CLARENCE “from a more progressive order.” The nuns say a prayer and begin to eat dinner, but when Deloris complains, the nuns enthusiastically share all the reasons why they love being nuns (It’s Good To Be a Nun). Mother Superior and Deloris are left alone, and Mother Superior has a proposition: would Deloris like to join the choir? The singer quickly says she will. 

The next morning, Deloris arrives at choir practice and is immediately shocked at how terrible the choir sounds. The nuns, however, are amazed at Deloris’s musical talent. Taking the musical baton from choir leader MARY LAZARUS, Deloris reminds the nuns that they are “rejoicing” and “singing to the Lord.” She encourages the nuns to sing louder, to sing on key, and to blend with each other. By the end of the rehearsal, the choir sounds incredible (Raise Your Voice).

The choir continues to impress at the next church service, where they draw crowds the church hasn’t had for a long time (Take Me to Heaven – Nun Choir Version). But now everyone is impressed by the choir’s new sound—Mother Superior calls Eddie to the church, asking him to take Deloris away. Eddie relays this command to Deloris, who is frustrated and concerned that Curtis will find her. She is disappointed with Eddie, and Eddie wishes desperately that he could be her knight in shining armor (I Could Be That Guy). 

Deloris approaches Mother Superior about the choir, trying to get her to understand their performances could be beneficial to the church. Mother Superior disagrees… until Monsignor O’Hara reports that the church is receiving a large number of donations. Mother superior agrees to keep Deloris in the choir, and the next church service is even more energetic than the previous one (Sunday Morning Fever – Part 2). Positive publicity flows in, and the choir is even invited to perform for the pope! The nuns are ecstatic. However, all the publicity has a price—Curtis and his thugs recognize Deloris on TV. They hatch a plot to get into the convent and steal her away (Lady in the Long Black Dress). 

Right before their performance for the pope, the nuns nervously gather in Deloris’s room. They ask her to lead them in a blessing, and she does (Bless Our Show). Suddenly, Mother Superior bursts into the room, telling Deloris she is in danger and must leave. The nuns are confused—who is Deloris? The musician reveals her true identity and the reason she has been staying in the convent. Though the nuns are shocked and saddened by the news, sweet young postulant MARY ROBERT approaches Deloris and asks to go with her. The young woman is beginning to doubt being a nun is her true calling (The Life I Never Led). Deloris tells her she can’t make Mary Robert’s decision for her; she must figure that out herself. Mary Robert leaves Deloris her rosary, and Deloris expresses her wish to stay with her sisters (Sister Act). 

The nuns are rehearsing for their performance for the pope when Deloris walks into the room. She has chosen to perform with them, and the nuns are overjoyed. But their joy is quickly interrupted when they hear the sound of a window breaking. Curtis has come for Deloris! The nuns scatter, attempting to hide their sister. After a few minutes of antics, Curtis corners Mary Robert, and Deloris steps in to protect her. With her sisters behind her and Curtis coming for her, Deloris kneels and prays (Sister Act – Reprise). Curtis crosses to Deloris, ready to strike, when Eddie jumps out from the middle of the nuns, surprising the thug. The cops handcuff Curtis and take him away, and Deloris rewards Eddie with a kiss. Mother Superior asks if Deloris will come back to the church to visit, and Deloris says she will be back often to sing. The sisters end the show with a rousing performance for the pope (Spread the Love Around).