As with the first film in the series, The Dark Knight took inspiration from Frank Millers seminal comic Batman: Year One. Having Batman save James Gordons son from a potentially lethal fall is an obvious nod to Millers opus, but theres another, smaller one earlier in the film, when Bruce Wayne, operating during the day time, dons a motorcycle helmet and jacket to stop the Joker from assassinating Mayor Garcia. Bruces motorcycle outfit bears a suspicious resemblance to the motorcycle outfit Bruce wears during Year Ones climax