Josh Brolin looks at Paul Thomas Anderson as a brother.

The 46-year-old actor stars in the director's upcoming drama Inherent Vice, playing Det. Christian 'Bigfoot' Bjornsen. Josh appears alongside the likes of Joaquin Phoenix, Owen Wilson and Reese Witherspoon and the cast soon felt like a family on set, bonding over their common interests.

"I was like, 'This guy works with the greatest actors out there.' And that’s it. Even seeing [Paul's film] The Master, I just thought it was amazing. When I saw it the second time and a third time, I thought it got better and better and better for me," Josh gushed to Collider.

"So, in my mind... you just kind of don’t sound like, 'Oh I’d really like to work with Paul Thomas Anderson.' It’s just like, 'That’s probably something that’s not gonna happen.' And then you get a call saying, 'Look, I think I may have some work for you.' Which was the line, and then it works out.

"Then you’re on set with this guy and he’s like your brother. And I don’t mean your bro, I mean actually like your brother, and you’re like, 'Oh, we grew up together, we understand the same things, we have the same references. We appreciate a lot of the same absurdities and we see the humanity in those absurdities."

Joaquin plays investigator Larry 'Doc' Sportello, who looks into the disappearance of his ex-girlfriend's boyfriend. The stars got along like a house on fire and had a similar approach when tackling the dramatic roles.

"I know actors that hate improvising – not that we improvised a lot in this. I think we emotionally improvised, behaviourally improvised but some people don’t like that. Plus, by the way, I like to learn a script before I start," Josh explained. "I know the whole script before I start the movie. But knowing that Paul may rewrite and this and that but I know the foundation. I don’t feel like I can work on what I want to do unless I know the whole thing."

LATEST NEWS