Transcript for Alec Baldwin opens up on new memoir, past addiction, playing Trump
Alec Baldwin's impression of president trump is so iconic that an international newspaper once mistakenly used a photo of him dressed in his "Snl" wardrobe for a cover story about the actual president. Alec explains why that impression is in fact quite discomforting for him and opens up about the darker moments in his career. Here's ABC's George Stephanopoulos. Thank you for coming. I'd like to start by answering the question on everyone's mind. Yes, this is real life, this is really happening. His iconic portrayal of president trump on "Snl" is Alec Baldwin at his most piercing. No, no refugees. America first, Australia stuck sucks, your reef is failing, prepare to go to war. Where do you find your inner trump? To me I wanted to do this caricature. The goal was to make trump something very simple and very clear. Right away trump walks out and he's vulgar, he's kind of ugly, he's unhappy. The trump that I see never smiles. Take me to your leader! It's him! It's stressful to play him? It's stressful because it's not somebody who I am in love with. I don't mean to bash him constantly but trump is not someone I admire or supported him in any way in terms of his politics. So when you do him, it's tough to do someone, to kind of get into that zone of someone who's very caustic, very unpleasant. Reporter: President trump hasn't been pleased either tweeting, the Baldwin impersonation just can't get any worse, sad. I think the Alec Baldwin situation is not good. Reporter: And Baldwin's wildly popular run on "Snl" is just the latest chapter in a show business career that's Stan spanned three decades. I've always been not interested in people's survival stories in the business. When I was young, I've been in this business 40 years! Okay, great, good for you. Reporter: Now 59, Baldwin's reflecting in his new memoir "Nevertheless." My sense from reading the book, correct me if I'm wrong, in some ways you're an accidental actor. I think I am, interesting you said that. I think I am in terms of I went into this business and I remember saying to myself, to my dad especially, I said, I'll give this a year. And if I have some provocation, if I have some encouragement to go further, I'll keep going so long as I have some motivation to do so. Let's talk about something important. Reporter: Motivation that propelled him in movies like "Glengary Glen Ross." Put that coffee down. Coffee's for closer only. Reporter: In a TV series he calls the best job he's ever had, "30 rock." Money can't buy happiness. It is happiness. The show was the best opportunity of my life at the same time, I kind of find of strange, even in the book itself, the publishers put the word comedian in there. You don't think it's funny? I don't view myself as a comedian. What I do on "30 rock," that's acting. People who are funny write the material. Tina's funny, she writes that. There are no bad ideas, only great ideas that go horribly wrong. I'm very grateful that whatever ability I had to read a line could coincide with and intersect with her writing. Reporter: Baldwin is blunt, candid, self-aware, reflecting back on his earliest years growing up in middle class long Island, New York. You go back to your childhood. Vivid, vivid memories of your childhood. Also the pain you saw in your father's life. I was obsessed with work and making money because of my dad. I wanted them to be happy and they were crushed by debt and money. That really drove me nuts. I remember I would go, got to make money, got to make money, don't want to be like my dad. Any money choices you regret? Oh, sure. Reporter: One of his first big role in the 1980s was on "Knots landing." I'm his son. His son. Reporter: That role coincided with addiction to alcohol and cocaine that he says nearly killed him. What if you hadn't stopped drinking on February 23rd, 1985? That's a good question. I was one of the people who was lucky that it stuck. And therefore, if I didn't get it then, I would have gotten it eventually. I got sober when I was just about to turn 27. And those two years that I lived in that white hot period as a daily drug abuser, as a daily drinker, to my misery, boy, that was a tough time. It was really, really a lot of pain in there. Reporter: Baldwin got seasoner and his biggest movie yet in 1990. He intends to defect. Anybody who's self-aware and has had success in life knows luck has a lot to do with it. What was your break? "Hunt for red October," to star in a big film, that changed everything for me. That was the base point? Boy, you confront what happened after "The hunt for red October" when you didn't get the sequel. It looks like I kind of jumped off a cliff. And here comes Harrison Ford. Right, that it was my own doing, which I wanted to explain that was nothing, they had completely engineered something. Reporter: Baldwin writes the film's producers went behind his back to cast Harrison Ford for the sequel, cutting him out of the franchise entirely. Hard to be friends with Harrison Ford after that? Yeah, I mean, in terms of I explained very vividly in the book how he's someone who was a completely different kind of career than I. Mega movie star career, no doubt, I'm not diminishing that. But I think he makes his choices based on an entirely different set of values. Reporter: Life in the public eye has been tumultuous for Baldwin. I want to press charges against her. Reporter: Numerous run-ins with Paparazzi. What's changed so much in my lifetime is this not just advent but this growth of social media. Where it's a very slippery slope for celebrities. Especially if you have any kind of outspoken nature. Especially if you not slip and fall but trip yourself sometimes with some of the things I've been through. And it's tough to survive. Reporter: His most painful public scandal, that infamous voice mail left for daughter Ireland in 2007. That voice mail you say caused a permanent break in that relationship. Permanent? I think that permanent insofar as -- I don't think anybody ever recovers from things like that. It's thrown in your face every day. As I mention in the book, there are people who admonish me or attack me or spit on me and use that as a constant spearhead to do that. It's a scab that never heals because it's being picked at all the time by other people. My daughter, that's hurt her in a permanent way. Reporter: For all his stumbles along the way, today Baldwin says he's living his dream life, both in his career and at home with his wife elaria and three young children. As you wrap up the book and talk about elaria and your little kids, you're about as happy as you've ever been. You talk about in the business, you've got to be lucky. I have been lucky to some degree. I'm luckier in my personal life. And I'm glad that I'm luckier in my personal life. I'm lucky in my family life. Fy had to choose, I'd pick that. Reporter: For "Nightline," I'm George Stephanopoulos in new York.
This transcript has been automatically generated and may not be 100% accurate.