LOS ANGELES—Although Adam Sandler had already earned good reviews for his work in the dramatic film Punch Drunk Love, he realized from his first read-through of the script for a film called Reign Over Me that making the movie would be extremely challenging. In a Los Angeles hotel room, he says he could see that playing the role of Charlie Fineman, a man whose wife and three children died on September 11, 2001, would take him to emotional places he had not been before. (The film opens next Friday [March 23].)

“The first time I read the script, I thought it was pretty incredible, but I was scared of it,” he says. “Then I read it a month later and it was very moving and I just couldn't stop thinking about it. I wanted to challenge myself. It hurt my heart when I first read it, and I wasn't sure I could do it. I was pretty sure that I could do everything that was needed on Punch Drunk Love, and if I was unsure the director would tell me I could do it and I would just do it. But here, every time [director] Mike [Binder] said I could do it, I would think, ”˜I hope I can do it, because I don't want to let anyone down.' It was painful, but I knew it was important to feel as much as I could, so I tried to be prepared every day. It wasn't like my comedies, where I could laugh and have a great time on-set. It was definitely heavier for me.”

Sandler's dedication to the role impressed Binder, who says that although he knew the comedian could do drama, he didn't think of him as being someone who would be dedicated to getting the character right. “The job that Adam had to do was layered in its complexities, and at the same time it was very simple,” Binder says. “I was so impressed with his work ethic and his ability to completely dive into the water and do what it took to do to become this character. He would call me late at night and ask, ”˜Does my guy think like this? Would he do this?' and I would say, ”˜When I get up tomorrow morning, I might be able to help you with this.'?”

In the film, Charlie eventually goes to see a psychiatrist (Liv Tyler) in order to deal with his postttraumatic stress disorder. Sandler says that although he usually doesn't do a lot of research, he spent a lot of time trying to understand his character's illness. “I sat in some therapy sessions as people were going through them. I would only sit in if they were okay with it, and if not I would leave. It was tough sometimes because some of the people had gone through 9/11 and, like him [Charlie Fineman], they were still going through it five years later.”