On 5 October 1857 she took the part of Pauline in Edward Bulwer-Lytton's Lady of Lyons at the Haymarket Theatre in London.

[2] Sedgwick's further roles at the Haymarket included Constance in The Love Chase by Sheridan Knowles, Hester Grazebrook in The Unequal Match by Tom Taylor, Beatrice in Shakespeare's Much Ado About Nothing, Julia in The Hunchback, Lady Teazle in The School for Scandal, and Juliana in The Honeymoon.

In 1869 she was allowed to direct herself in the play Pindee Singh, the Pearl of Oude by C. H. Stephenson, which was the opening performance of the Royal Albert Theatre.

Her comic interpretation of the Dickens character "Sergeant Buzfuz" was a favorite performance in this part of her career.

[4] French writer Henri-François-Alphonse Esquiros described Amy Sedgwick's appearance in 1862 as "not a Greek beauty, but a true English beauty, tall and well filled out, with an intelligent mouth and forehead, blue eyes, hair of golden auburn, firmly and yet delicately pencilled eyebrows, teeth of irreproachable whiteness, and a peculiar art of conquest.