Conversation so far:
What is an example of a job Henry Irving held early in his career?
Irving became a clerk to a firm of East India merchants in London
What year did Henry Irving first start to act?
On 29 September 1856 he made his first appearance at Sunderland as Gaston, Duke of Orleans, in Bulwer Lytton's play, Richelieu

Question: In what work did he make his first acting appearance?
Self-contained rewrite: In what work did Henry Irving make his first acting appearance?