Chisnall is currently understudying the role. Among his other West End credits are Love Never Dies, La Cage aux Folles, Never Forget, Evita, and The Woman in White.
McDermott may be best known for his portrayal of Ryan Malloy on the television series EastEnders. His stage credits include La Cage aux Folles at the Menier Chocolate Factory, and Follies and The Sound of Music in the West End.
The show, which is based on the story and characters from William Steig's book Shrek! as well as the DreamWorks Animation film Shrek, features book and lyrics by Pulitzer Prize-winner David Lindsay-Abaire, and music by Jeanine Tesori.
In addition to Lindsay and Harman, the show also currently stars Kimberly Walsh as Princess Fiona and Richard Blackwood as Donkey.
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