The Spectre Knight is a one-act "fanciful operetta" with a libretto by James Albery and music by Alfred Cellier. It was first performed on 9 February 1878 at the Opera Comique by the Comedy Opera Company as a companion piece to The Sorcerer. The piece continued to run until 23 March 1878 and was revived by the company from 28 May 1878 to 10 August 1878 as a companion piece to H.M.S. Pinafore. The piece had a run in New York in 1880 and was toured in Britain and America.
No libretto appears to have been published. A copy of the vocal score, published by Metzler, is in British Library at F.739. The vocal score contains no dialogue, although it has a synopsis of the plot. The licence copy of the libretto is in Lord Chamberlain's collection at Add. MS. 53199, Play no. H, Jan–Feb 1878.
The fashion in the late Victorian era was to present long evenings in the theatre, and so producer Richard D'Oyly Carte preceded his Savoy operas with curtain raisers such as The Spectre Knight.W. J. MacQueen-Pope commented, concerning such curtain raisers:
The Spectre Knight is a particularly long curtain-raiser, with sixteen songs, and running over an hour.
The eccentric Grand Duke, with his daughter Viola and the remains of his court, has been banished and live in a lonely glen where they try to keep up the semblance of their former grandeur. Viola has known no other life and never seen another human being except those of their party. She is thus greatly delighted when the Duke's nephew Otho arrives in the glen disguised as a friar. Otho falls in love with his cousin at first sight, and having learned from her of the legend of the spectre knight who is supposed to haunt the glen, he appears in the disguise of the ghost. He wins Viola's heart and finally introduces himself to her as Otho who has just overthrown the usurper of her father's throne. He promises that they can all go home again. The Duke consents to Otho's union with Viola, and all ends happily.