I had a period when my career started taking off and I started to get better opportunities. Freaks and Geeks had ended. I was struggling, and then I auditioned for James Dean and got cast as James Dean. I auditioned with Robert De Niro and got cast in City by the Sea. I auditioned for Spider-Man. I didn’t get Spider-Man but I got the friend role, not a role that I had been dying to do, but in one of the biggest movies of all time. So I had a role in the James Dean movie that was very satisfying to an actor, a role with De Niro who was one of my heroes, and a commercial movie. All three came out around the same time. After that, people were offering me movies. I had choices. That was a scary moment, because up until then, you just take what’s given to you. You’re happy if you get a job, and you’re really happy if it’s a good job.

I turned to my teacher for advice. I had an acting teacher I had worked with for years, and when everybody else told me not to do James Dean, he was the only one who said, “Do it.”

He helped me prepare for it too, because he was obsessed with James Dean. He said isolate yourself, don’t talk to your family, don’t talk to your friends, don’t talk to your girlfriend, start smoking, you have to watch one of the James Dean movies every day, maybe two of them, read all the biographies, meet all the people who knew him who are still alive, look at all the photographs, get the poses down, experiment with men, listen to his voice in your car all the time, race cars, go to the zoo, look at the monkeys—because he kind of moves like a monkey—study the chimpanzees, do all that, anything and everything you can.

Because of that, in my young head, I thought, He knows, he has the secret. He knows what to do when everybody else doesn’t. I started going to him about which movies to pick.

When Tristan & Isolde came along, I wasn’t into it. It was directed by Kevin Reynolds, who’d made Waterworld and Robin Hood. I thought maybe we weren’t the right people to work together. I could feel that when I first met with him. Before the meeting, I read up on the legend, and listened to the opera, and his script was different. No love potion causes Tristan and Isolde to fall in love. Isolde doesn’t die.

In the meeting, I asked Kevin something like, Why have you decided not to kill Isolde? I wondered why some choices had been made. He said, “I don’t know, James,” like that was in the hands of the authorities.

I went back to the teacher and said, “I’m not getting a good vibe.”

My teacher replied, “The actor never knows. The actor never knows.” Meaning, the actor doesn’t know what to choose. The actor doesn’t know what’s good for him. In the studio days, roles were picked for the actors, and that made for better movies. It was like a factory. They kept putting them out and you were under contract, and you had to do what the studio said, more or less. Unless you were a big star, and even then you had to do a certain number a year.

“This is a role that a young Olivier would do, that a young Brando would do,” he told me. It didn’t seem right to me, but I thought, Maybe it’s kind of heroic, like Braveheart. There were all these huge, tough battle scenes in it. So I said I guess I’ll do it. It was a young leading-man type of role.

The thing was, I had eight months from when I signed on until we started shooting. I had learned from doing James Dean to prepare in a way that was immersive. When I signed on for Tristan, I thought, I have to do everything. Tristan’s from Cornwall. I got a dialogue coach and worked on Shakespeare. There were sword-fighting scenes and battles on horseback. I thought, I’ve got to learn how to ride a horse. I had never really been on a horse besides dinky trail rides. I started riding every day, seven days a week, right by Hollywood. I went to a father and son named Sled Reynolds and Titus Reynolds, who have great horses that are used in movies—like the horses in Zorro, these Friesians—and beautiful white Andalusians. We rode all over Griffith Park—into the sunset, that kind of thing.