The 36-year-old Suicide Squad star was on the receiving end of blows from his dad as a teenager, but he still has nothing but love for him.

“We’re good now," he tells Mr. Porter. "I’m working on a film about his life with a Swedish director. I’m going to play him."

Joel's compassion for his dad comes from his belief the beatings were prompted by learned behaviour passed down through generations.

"He was beaten by his parents, too," he explains, "and in my teenage years, I was definitely testing the boundaries... hanging out and smoking weed. I had a lot of anger in me, and I was insecure. I was really skinny and I used to get bullied, so it felt good to bully other people. That made me feel stronger."

Joel was born and raised in his mother's native Stockholm, and The Killing star admits he was hanging out with the wrong crowd during his high school days.

"I wasn’t afraid of getting hit, because my head got rung at home," he recalls, noting his friends at the time were rough criminals who would make it difficult for him to leave them behind. "Every time I saw them on the street, I had to fight them. And if they saw my new friends, who I played soccer with, they would rob them and beat them up, but leave me alone.

"It was really hard. I had a lot of anxiety. I couldn’t eat."