As previously announced, Tony Award winner Beth Leavel (The Drowsy Chaperone) will succeed Carolee Carmello in the role of Donna Sheridan, and Gypsy Tony nominee John Dossett will step into the role of Sam Carmichael Sept. 22.
Louis, who will be making her Broadway debut, will play bride-to-be Sophie Sheridan with Morris (Coram Boy) as her fiancé Sky. Boll (Faith Healer) and Macdonald ("Guiding Light," Coram Boy) will join the company as, respectively, Bill Austin and Harry Bright.
Continuing in their roles are Judy McLane (Tanya), Gina Ferrall (Rosie) and Ben Gettinger (Pepper) with Samantha Eggers as Lisa, Amina Robinson as Ali and Raymond J. Lee as Eddie.
Mamma Mia! features music and lyrics by Benny Andersson and Björn Ulvaeus, a book by Catherine Johnson, direction by Phyllida Lloyd and choreography by Anthony Van Laast.
Mamma Mia! became the 14th longest-running show in Broadway history Aug. 2.
The Winter Garden Theatre is located in Manhattan at 1634 Broadway. For more information visit www.mamma-mia.com.