The story is about a twelve-year-old boy, Dennis, who enjoys wearing a dress and the reactions of his family and friends.

[1][2] The musical is based on the 2008 novel The Boy in the Dress, which was written by David Walliams, with illustration by Quentin Blake.

[4] In February 2018, Gregory Doran, artistic director of the Royal Shakespeare Company, confirmed that the RSC was working with David Walliams on an undisclosed project.

On 22 August 2019 the initial adult casting was announced including Rufus Hound as Dad, Natasha Lewis as Darvesh's Mum, Forbes Masson as Mr Hawtrey and Irvine Iqbal as Raj.

To launch the album, the RSC live streamed an event called The Boy in the Dress: A Celebration on 5 December 2020 which featured author David Walliams reading from the original novel and co-songwriter Guy Chambers performing songs with Toby Mocrei and Miriam Nyarko (reprising the roles of Dennis and Lisa James respectively).