Dirk Gently is a fictional character created by
Douglas Adams and featured in the books
Dirk Gently's Holistic Detective Agency and
The Long Dark Teatime of the Soul. (Adams was working on a third Gently novel,
The Salmon of Doubt, at the time of his death.)
Dirk bills himself as a "holistic detective" who makes use of "the fundamental interconnectedness of all things" to solve the whole crime, and find the whole person.