Langford is currently playing Dorothy Brock, almost 25 years after playing Peggy Sawyer in a national tour of the show.
Langford's other theatre credits include Cats, Spamalot and Chicago, and has most recently been seen on TV in EastEnders.
42nd Street is the revival production of the show which follows the lives of performers as they struggle to make their names on Broadway. The piece has a book by Michael Stewart and Mark Bramble, music from Harry Warren and lyrics from Al Dubin and is an adaptation of the 1932 novel and the 1933 film.
In her review, Sarah Crompton called the show 'the most sophisticated and joyful of backstage musicals'.