Mr Sullivan cleverly uses the rat as a way of burrowing into New York's hidden history and forgotten men, such as Kit Burns, a rat-pit impresario, who ran the city's most popular entertainment in the mid-1800s until cornered by crusading animal-rights activists.
In fact, last year TWU Local 100 ran a YouTube video noting that for every rat subway riders saw, there were 8-10 more in hidden areas throughout the subway system.