Against what some would consider incredible odds, Sleepy Hollow was renewed for a fourth season in May, and the show has been retooling the hell out of itself ever since. It will be re-set in Washington, D.C.; Ichabod will have a new partner
and villain
to contend with; and now there are three new supporting characters.
Source: io9 – Sleepy Hollow Can’t Stop Adding New Cast Members Ahead of Its Fourth Season