© Rex Features
The drama will focus on Annie Travers, a female cop who discovers a magical world that exists within New York.
British actor Sloane - best known for his roles in UK soaps Hollyoaks and Brookside - will play detective Boyo, according to Deadline.
A denizen of Gotham, Boyo becomes Annie's new partner when she arrives in the magical world.
The River's Michael Green has written the Gotham pilot, which will be helmed by I Am Legend director Francis Lawrence.
Other drama pilots in development at ABC include a Beauty And The Beast update and a sci-fi project starring Martin Landau.
A remake of Dutch crime series Penoza and Devious Maids from Desperate Housewives creator Marc Cherry are also in the works.
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