The 40-person cast features Drama Desk Award winner Jan Maxwell as villainess Mrs. Lynch, Jolly Abraham (Bombay Dreams) as Molly, Uzo Aduba as Toby, Jacqueline Antaramian (Julius Caesar) as Mrs. Hendry, Bill Camp (Heartbreak House) as Otis Gardiner, Dashiell Eaves (The Lieutenant of Inishmore) as adult Thomas Ledbury, Xanthe Elbrick as Young Alexander Ashbrook/Aaron, Tom Riis Farrell (Dirty Blonde) as Mr. Claymore, Brad Fleischer (Pig Farm) as Meshak Gardiner, Karron Graves as Isobel Ashbrook, Laura Heisler as Edward Ashbrook, Angela Lin as Miss Price, David Andrew Macdonald (Two Shakespearean Actors) as Lord Ashbrook, Quentin Maré (Julius Caesar) as Frederic Handel, Kathleen McNenny (The Constant Wife) as Mrs. Milcote, Cristin Milioti (The Lieutenant of Inishmore) as Alice Ashbrook, Charlotte Parry (The Real Thing) as young Thomas Ledbury, Christina Rouner as Lady Ashbrook, Ivy Vahanian as Melissa/Angel and Wayne Wilcox (Suddenly Last Summer) as adult Alexander Ashbrook.
Also part of the cast is a 20-member onstage choir, which performs Handel's "Messiah" as well as original music composed by Adrian Sutton. The choir includes Philip Anderson, John Arbo, Sean Attebury, Renée Brna, Charlotte Cohn, Sean Cullen, Katie Geissinger, Zachary James, Tinashe Kajese, Katherine Keyes, Evangelia Kingsley, bj Karpen, Eric William Morris, Samantha Soule, Daniel Neer, Nina Negri, Mark Rehnstrom, Martín Solá, Alisson Weller and Greg Wright. The singers are backed by a seven-piece chamber orchestra.
Adapted by Helen Edmundson from Jamila Gavin's award-winning novel, Coram Boy features direction by Melly Still. The creative team also includes Ti Green and Melly Still (designs), Paul Constable (lighting design), Adrian Sutton (music), Christopher Shutt (sound design), Constantine Kitsopoulos (music director) and Thomas Schall (fight director).
Set in 18th-century England, the production, according to press notes, tells the tale of "two orphans at the Coram Hospital for Deserted Children: Toby, saved from an African slave ship and Aaron, the abandoned son of the heir to a great estate."