Answer
The play in which Colin Morgan appeared is "All About My Mother", a Pedro Almodóvar play based on his 1999 film of the same name. Directed by Tom Cairns, its cast includes Morgan as Estéban, Hayley Atwell as Manuela, and Janie Dee as Huma Rojo. It examines themes of motherhood, gender identity, and loss, mirroring the movie's exploration of these complex and emotional subjects.