Hmm... lemme see here... We have one crochety old detective, one young cat burgler, one distinguished professor of science from Miskatonic university, one person whom I know but will not reveal (Ashy), and two undeterminates in the form of Joshua Dyle and yourself.
Perhaps you are a doctor or orderly at Arkham Asylum, one of those that have cared for Dr. Whitherspoon during his lengthy incarceration. You know the old coot well, and he's gotten rather contemplative in his dotage. His fantasies that drove him to burn down the previous asylum he has taken to writing down in a series of nigh-incomprehensible books, which is rather preferable to his former ranting and raving. He's mostly harmless, as long as no one brings up the situation that brought him here, or tries to take him into the basement for treatments.
Or perhaps you were one of the orphans that benefited from Dr. Whitherspoon's charity as a youth. Now you could be a student at Miskatonic unversity, following in Dr. Whitherspoon's line of research. Or perhaps you're a fisherman down at one of the coastal towns, just another working man. You could even be something as simple as a janitor at the university, one that slakes his thirst for knowledge while cleaning in the library late at night.
Any of those trip your trigger?