Cara Delevingne was "obsessed with blood and death" as a child.
The 23-year-old supermodel and actress admitted she was "really dark" when she was younger and almost cut off her finger when she tried to shave like her dad.
She told W magazine: "When I was a child, I was obsessed with blood and death. This sounds really dark, but my earliest memory is of cutting myself. I was pretending to shave like my dad.
"One time, I covered my face in shaving foam, and I got his razor and ran it along the bottom of my finger and nearly cut it off... [The scar] is barely visible now. But I like knowing that it's there."
Meanwhile, Cara also revealed she walked around a forest naked while howling like a wolf to prepare for 'Suicide Squad'.
The star plays villain Enchantress in the upcoming superhero movie and has revealed she landed the part by getting angry at director David Ayer in her audition, and he advised her to stroll around a wood pretending to be a wolf during a full moon.
She said: "Somehow, when we were doing the scene, I became livid. I hadn't felt rage like that in years. And then I got the part!
"There still wasn't a script, but David asked me to go and try and find a forest and, if it was a full moon, get naked and walk through the woods with my feet in the mud, which I did. There wasn't a full moon, but I howled like a wolf.
"It would have been really funny if someone had seen me."
The first time the British model met the filmmaker he didn't even speak to her about the movie, instead he got her in the mindset for the role by showing her images of "evil women".
She added: "I met the director, David Ayer, at a hotel in London on a dark and stormy night. He didn't tell me anything about the movie.
"Instead, he showed me pictures of these amazing, enlightened, powerful, but very evil women. He spoke to me about addiction and mental illness, which are things I find very, very interesting."