Theatre includes: Scarlett recently performed at the Night of 1000 Voices concert at the Royal Albert Hall after finishing the scheduled run of her Royal Shakespeare Company debut playing Anne Page in Merry Wives the Musical. Prior to that she played the title role in Mary Poppins and Josephine in the New Shakespeare Company's production of HMS Pinafore at Regent's Park Open Air Theatre. Other productions for the New Shakespeare Company include Cymbeline and Twelfth Night. Other credits include Truly Scrumptious in Chitty Chitty Bang Bang at the London Palladium, and original casts of Mamma Mia! at the Prince Edward Theatre, The Witches of Eastwick at the Theatre Royal, Drury Lane, and Peggy Sue Got Married at the Shaftesbury Theatre. Scarlett also appeared as Jenny in Aspects of Love and Jessie in Annie Get Your Gun, both at the Prince of Wales Theatre.

Television and film includes: No Sweat! for the BBC, and the film Beyond the Sea directed by Kevin Spacey. Scarlett's voice can be heard on numerous talking books and animations.