

When Alan Cumming first read the script for "Any Day Now," some lines gave him pause. "I thought, 'Ew, that's a little overly sentimental,' " he says. "Do I really need to say that?"

Set in 1970s Los Angeles, the film concerns a gay couple: Rudy, played by Mr. Cumming, is a drag-queen cabaret performer; Paul (Garret Dillahunt) is an assistant DA. They keep their relationship closeted as they fight to adopt a boy ( Isaac Levya ) with Down syndrome after his drug-addicted mother goes to jail.

Actor and singer Alan Cumming Getty Images

The Scottish actor, 47, is best known for his stage work—he won a Tony for "Cabaret"—but also for film and TV roles (he's currently on "The Good Wife").

One of the most striking moments in "Any Day Now," which won several audience awards at film festivals, is when Mr. Cumming sings Bob Dylan's gospel-influenced "I Shall Be Released." The performance was so emotional that the filmmakers decided to tone it down in editing. Audiences tear up anyway.

The film will be released in 18 cities on Dec. 14. Edited from an interview.

Did you worry the script was too melodramatic?

After the first reading, I was like, "Oh, that can be a little schlocky or tacky." And even when we were on the set, I'd say, "Do I really need to say that?" And Travis [Fine, the director] would say "No." Now, some of the emotional parts are heartbreaking, but not overly manipulative. So, it was always a worry—and rightly so—at the start. I realized that what you do in early drafts is you overwrite.

So you'd suggest revisions?

Yes. I felt when we got to the script we started to shoot with, it was in good shape, but then you've got to see it in the room with other people and it feels different. Garret and I were both so impressed with Travis saying, "You know what? Don't say that." He was working too hard, milking a scene too much. The whole thing was a real lesson in economy.

Were you concerned Rudy was too flamboyant?

Yes, I was worried about how I made the character more effeminate-y, that's not a word. It's always a worry when you do something clichéd and perhaps not the most positive representation of a gay person. Yet also, there was this toughness to [Rudy]. Even though he was a drag queen, I thought he is tough. Drag queens are some of the toughest people I've ever met. Because if you're a man and you're going to parade around in high heels and a wig, you'd better be.

You look very skinny in this film. Did you lose weight for the role?

I had just decided to stop drinking for a while. Then I realized in all the pictures I looked at that everybody was much skinnier in the 1970s, because probably they all smoked and there wasn't such a proliferation of processed foods. So, I was losing weight and I thought that the not-drinking would kind of help with that. And I went to the gym a lot. [After shooting was complete] I took my mother on the Queen Mary across the Atlantic. And I realized there was no way I could spend a week at sea with my mother without alcohol involved.

Tell me about when you sing "I Shall Be Released."

It's an amazing thing to be able to do as a performer, to sing a beautiful song like that, but also to imbue it with such emotion and pain. That communicates so much to the audience without actually being part of the story. Of course, it was like, "No pressure!" I was feeling very vulnerable singing in that way. The really scary thing was that I didn't know the song, so [Mr. Fine] sent me a video from YouTube of Bette Midler singing it in a bathhouse with Barry Manilow playing the piano for her. It was all about the level of how much she would lose it. [After editing], you see me trying so hard to keep it together. That's more moving than someone losing it.

It sounded sort of Elton John-ish.

I know what you mean. But I didn't mean to. Unless I am impersonating someone, I just kind of do it. That's interesting. It's the right period. I heard the Jerry Garcia one, too. I heard a few, and was like, I can't deal with this. When it's Bob Dylan, Jerry Garcia and Bette Midler—and then you have to actually do it in a way that's you and in character and all that—so I just stopped. I made sure I knew the vague tune. When the day came to do it, I wanted it to be heartfelt and raw and kind of spontaneous.

Had you ever worked with an actor with Down syndrome before?

No. It was another one of these things where I thought, I have no idea what this will mean to the day-to-day work. I had no idea what type of relationship I would have with him. The first day I met him, he was excited because he had seen "Spy Kids." We chatted, and he told me about his favorite film, which was "High School Musical." He sang this song in its entirety just looking in my eyes, and it was just amazing. I just fell in love with him that afternoon.

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