Bruce Wayne, what's happened?!
The Batman himself, Christian Bale, was spotted on set of the "Untitled David O. Russell / Abscam Project" in Boston on Thursday ... and he is not looking his finest.
The (typically) handsome 39-year-old looked more like Tom Cruise as Len Grossman in "Tropic Thunder" than the dapper billionaire playboy / crime fighter from "The Dark Knight."
Bradley Cooper was also seen on set earlier in the week -- thankfully looking normal, which is good for him as he was hanging out with a possible new lady love.
The film is based on a real-life FBI sting operation from the '70s, and also stars huge names like Jennifer Lawrence, Amy Adams, Jeremy Renner and Louis C.K. It hits theaters this Christmas.
Bale's not the first film star to undergo a huge makeunder for a role. Click "Launch Gallery" above to see celebs like Colin Farrell, Ryan Reynolds and Charlize Theron also get ugly for the job.