 Percy studied law, but instead decided to become a journalist, contributing to such journals as "Punch", "The Sketch" and "The Tatler", and to write for the theatre.After Harry's death, George Edwardes asked the younger Greenbank to collaborate with Adrian Ross on the lyrics for "The Messenger Boy" and also interpolated two of his lyrics into "San Toy" when that score was revised ("Somebody" and "All I Want is a Little Bit of Fun").He began to collaborate with composers Ivan Caryll and Lionel Monckton, as well as with Ross and the deviser of the Gaiety show plots and outlines, James T. Tanner.