Talk about method acting… Scott Siegel, an actor who played a steroid dealer on the show “The Wrestler” was busted… for selling steroids! Maybe he was doing research for a role, if that’s the case I shudder to think what Anthony Hopkins had to do for research on role HE played!
Siegel led police on some huge bollucky chase where he tried to slam into police cars and hit pedestrians, he probably tried to hit old grandmothers pushing babies in carriages or something as well.
I’ve known some INSANE actors in my time that get way too into their 
roles. One woman I knew would stress herself out so much to play her part she would hyperventilate between scenes and go a bit nuts, as if the scene had never ended.
Another man I knew, not an actor per say but more like a “life performer”. I had the honor of meeting composer Mark Adamo after a performance of Lysistrata at the Seagle Music Colony in upstate New York. The man was AMAZING, he would flail about as he spoke, contorting his body into positions most yoga gurus would have trouble with. He wore bright button up shirts with bright white pants, and never shared a dull moment. The guy was wildly amazing.
Anyway, as he was leaving he walked by the group I was standing with, fluttered about and bid us all farewell, then got in his car and drove away. I was really disappointed that he didn’t sprout wings and fly away.