See Jake Gyllenhaal's Shocking Transformation [PHOTOS]

What happened to Jake Gyllenhaal?!? The normally hunky actor who notoriously broke Taylor Swift's heart looked incredibly thin at the Hollywood Film Awards last night (Oct. 21).

So thin it's scary, but don't fear, Gyllenhaal fans. Jake isn't sick -- he lost the weight for his role in the upcoming 'Nightcrawler' movie. "I think [I've lost] probably a little over 20 pounds, something like that," he told People on the event's red carpet.

Twenty pounds from his already slender frame is dramatic. Take a good look at his "before" picture above, taken last June. Then scroll down to see the new photos ... IF YOU DARE!