A. K. Barnaby

The fabulously wealthy Batman fan who is the owner of Batman Island, a private island off the coast of Gotham City where Barnaby maintains the world's largest collection of Batman trophies, films, and memorabilia. Barnaby, whom the text describes as "one of the richest men in the world," helps Batman and Robin apprehend a gang of diamond thieves on his island in October 1958.