Derby Day (light opera)

Derby Day is a 1932 three-act light opera, with music composed by Alfred Reynolds to a libretto by A. P. Herbert. Herbert wrote his text between March and May 1931, whilst on a trip to Australia, during the first run of his successful Tantivy Towers.

One contemporary review described the work as "mainly a Cockney opera", and praised the work as "topical in the best sense" and said of the music:

I do not know if Mr. Reynolds is himself a Cockney, but I do know that his Cockney music, particularly in the coster scenes, is the best that has ever been written.

In particular, the song for the tipster, "'Oo wants a winner for the big race tomorrer?", has been singled out for particular praise as a musical expression of the Cockney.