Bradley Cooper was at rock bottom. Then he had a "hard conversation" with Will Arnett.

If it wasn't for Will Arnett, there's a very high chance Bradley Cooper wouldn't be where he is today, or sober.

Earlier this year, The Hangover actor appeared on the SmartLess podcast, hosted by Arnett, Jason Bateman and Sean Hayes, where he got candid about his past battle with addiction, how it affected his career, and his journey towards sobriety.

In 2004, Cooper and Arnett were neighbours. Arnett popped by one afternoon to find Cooper still hadn't taken his dogs out to use the bathroom. It was 4pm.

He also asked the actor what he thought about a dinner they had been to the night before. 

Cooper remembered it going well, and him being funny at it, but Arnett said: "You were a real asshole."

"That was the first time I ever realised I had a problem with drugs and alcohol," Cooper responded. "And it was Will saying that to me, and I’ll just never forget it."

In fact, Cooper said his friend Arnett is "the reason" he went sober, adding: "He took that risk of having a hard conversation with me that put me on a path of deciding to change my life."

Bradley Cooper in 2004. Image: Getty.

"I was so lost," he continued. "And I was addicted to cocaine, that was the other thing... I severed my Achilles tendon right after I got fired-slash-quit [the TV series] Alias."

The Nightmare Alley actor confessed that it also didn't help that he had “zero self-esteem” at the time.

"You went through this metamorphosis before The Hangover. Having those realisations and having that change allowed you to - that's what opened you up and allowed you to be you," Arnett told him.

"I did have the benefit of that happening when I was 29," Cooper explained. 

"I thought I made it when I got a Wendy's commercial, and I called my dad saying 'I'm in a hotel that has a window that opens'. In terms of the made-it thing, that's when I made it. 

"But moving to Los Angeles for Alias, [I was] feeling like I was back in high school. I could not get into any clubs, no girls wanted to look at me. I was totally depressed.

"It wasn't really until The Hangover. I was 36 when I did The Hangover, so I got to go through all those things before fame even played into my existence on a daily level. So all that happened before any of that."

Arnett said that he's loved seeing the “difference” in Cooper in the years since then, adding: "It has been awesome seeing you in this place and seeing you comfortable."

"Nothing has made me happier," he added. 

Cooper further reiterated just how much their "hard conversation" changed his life.

"Quite honestly today I can sit in front of you and tell you I have self-esteem and it's not related to any outside thing. I didn't have that for 46 years," Cooper said. 

Fatherhood - the actor is dad to a daughter, Lea, with whom he shares with ex-girlfriend Irina Shayk - has also been transformative for him.

"Everything changed," he said. "Every single thing is absolutely shaded by or brought out in glorious colours by the fact that I get to be a father to a wonderful human being. 

"It's just the absolute greatest thing."

Feature image: Getty.