She performed on the stage in London from the age of ten, when she played the Gipsy Girl in Guy Mannering at the Surrey Theatre.
In 1834, at the Royal Victorian Theatre, Horton played Julia in a musical adaptation of Guy Mannering, Kate in Sheridan Knowles's melodrama The Beggar's Daughter of Bethnal Green, Romeo, Desdemona in Othello, and Oscar in Gustavus the Third.
She was a favourite of James Planché, Charles Dickens[3] and Madame Vestris and was known for her agile dancing and clear contralto singing voice.
The historian Paul Buczkowski wrote of her, "Horton brought a lively intelligence to her roles, and was almost as highly lauded in tragedy (for instance, as Ophelia in Hamlet and the Fool in King Lear) as in comedy.
The Athenaeum wrote: "The only striking novelty in the performance is the Ophelia of Miss P. Horton, which approaches very nearly to the wild pathos of the original in one scene, and is touching and beautiful in all.
During these years, she also appeared at the Theatre Royal, Drury Lane as Philidel in Henry Purcell's opera King Arthur (1842) and created the girl/boy roles of Myrtina/Fortunio in Planché's Fortunio and his Seven Gifted Servants (1843).
[citation needed] In 1843, the Morning Chronicle praised "the light, airy, and imaginative" quality of a piece performed by Horton, called "The Elfin's Revel", composed by Charles Frederick Hall.