In Shutter Island, Martin Scorsese’s latest thriller opening today, it's 1954 and Leonardo DiCaprio is a U.S. marshal investigating the disappearance of a woman from a mental institution off the Massachusetts coastline. Exec producer Laeta Kalogridis gave GCD a behind-the-scenes glimpse into the madness…

GCD: How was it filming in a shutdown mental institution in Medfield, Mass.?
Kalogridis: Fantastic. The atmosphere was freaky and I think it helped. Every time I sat down to write something it felt authentic.

GCD: Was there one moment from your time on set that was especially memorable?
Kalogridis: We were filming a fight scene, and it takes place where the most violent offenders were housed, and there’s a crazy patient who has gotten loose who tries to kill [DiCaprio’s character] Teddy. He’s holding him in this chokehold and Teddy just loses it, almost kills this guy because he’s so wound up and because the sense of what’s happening on the island is just crushing him and crushing his spirit. And I remember watching Leo just go insane and thinking this is really amazing. Because he was so lost in it, and it was a f---ing fantastic take.

GCD: Anything else freak you out?
Kalogridis: I just have to say three words: Jackie Earl Haley [who plays an inmate]. Speaking of people inhabiting characters. I mean, dude. You put him in an insane asylum, locked up behind bars; it is really powerful. Just watching the playback from the monitor was freaky.