Seamus Macintosh
Seamus came from a small village in the empire. A murderous undead was terrorizing the village and a cleric of the Raven Queen came to help solve the case. During the time she spent in the village, Seamus was so impressed by her that he wanted to be like her. When she left, he followed.
He spent the next twenty years in the church. Where he trained to be a cleric and later an investigator.
This eventually lead him to meet first Finn and then the other members of the current team.