DC Comics/Milk Processor Education Program
05/28/2008 AT 02:35 PM EDT
The latest celeb to appear in a milk ad is Christian Bale – in his complete Batman costume from The Dark Knight
– who encourages teens to drink three glasses of lowfat or fat-free milk daily. Bale, 34, costars
with Heath Ledger
, whom Bale called "intense" and "anarchistic" on the set.