Dirk Gently (born Svlad Cjelli, also known as Dirk Cjelli) is a fictional character created by English writer Douglas Adams and featured in the books Dirk Gently's Holistic Detective Agency, The Long Dark Tea-Time of the Soul and The Salmon of Doubt. He is portrayed as a pudgy man who normally wears a heavy old light brown suit, red checked shirt with a green striped tie, long leather coat, red hat and thick metal-rimmed spectacles. "Dirk Gently" is not the character's real name. It is noted early on in the first book that it is a pseudonym for "Svlad Cjelli".
https://en.wikipedia.org/wiki/Dirk_Gently