In the novel Hallowe'en Party, Desmond Holland is a sixteen-year-old youth. He and his friend Nicholas Ransom helped at the fateful Halloween party organised by Rowena Drake at Apple Trees. They were present during the preparations for the event in the afternoon and managed one of the games stalls during the party itself. Poirot later assigns him and his friend to assist him in his investigation. See the article for Nicholas Ransom for details.
Desmond is the younger of the two friends. He is described as having hair which is "ginger-coloured", with "a good deal of fluffy profusion about it". While his friend prefered black as his fashion statement, Desmond, when he meets Poirot, is dressed in a rose-coloured jacket, mauve trousers and a kind of "frilled shirting".