Read InStyle's Fruitvale Station Cast Interview

Octavia Spencer, Michael B. Jordan, Melonie Diaz, Ahna O’Reilly, and the rest of the cast of Fruitvale Station traveled around the world to promote their powerful film, from Cannes (shown) to Los Angeles to New York. Earlier this year, we caught up with them in Park City, Utah at the Sundance Film Festival, where the film went on to win both the Grand Jury Prize and Audience Award in the Dramatic category. "We're a really, really close group," Spencer told InStyle.com at the festival. And they had to be to work on such an intense drama. The movie depicts the true story of Oscar Grant (Jordan), a 22-year San Francisco Bay Area native killed on New Year’s Eve 2009 by a police officer responding to a reported fight on a subway platform. Written and directed by Ryan Coogler, the film follows Grant's last 24 hours with his family and friends, including his mother Wanda (Spencer), his girlfriend Sophina (Diaz), his daughter Tatiana (Ariana Neal), and his old friend Katie (O'Reilly). Scroll down to sit in on our conversation with the cast.

What drew you to this project?

Michael B. Jordan: "The story itself. I told my agents maybe a month or so before the project came across that I always wanted to do an independent film, I wanted to do a gritty indie. Something I could just sink my teeth into on an acting level. Big budgets are cool, I love studio films and those are awesome as well, but there's something about an independent film that reminds you why you are acting. Then, because of the story and the subject matter. That could’ve been me or my brother or my friends or somebody that I knew. It hit home a little bit. As an actor, sometimes you can't really voice your opinion, so I figured that this is the best way to express myself. There is also pressure of playing a real person—it raises the bar and pushes myself."

Octavia Spencer: "I would say the fact that it is addressing a situation that is becoming far too frequent—police shootings of men of color. But I love the way Ryan [Coogler] handled it because it’s not about finger pointing. It’s just really chronicling the last day of this young man’s life, and that is the way I think you have to look at this so it doesn’t become an accusatory us against them. It’s just we’re all the same. And it’s such a beautiful, beautiful story."

Ahna O'Reilly: "Well, first of all, Octavia Spencer, she called me up a couple days before they needed someone there and said, “Will you be a part of this?” I read the script and I was like, “I will be there now.” I was so moved by the script. Coming from the Bay Area, it was a story that I’d heard about when it happened but it didn’t become enough of a conversation, so I’m just really excited to be a part of the telling of this story."

Melonie Diaz: "I also felt like it’s so rare when you get to do something that’s so socially relevant. As an actress, you do projects and they’re very much non-fiction and fiction. I would get frustrated with myself for not being political enough or socially aware. [With this], the script is a really good piece of work."

What was it like working with this kind of cast?

Michael B. Jordan: "Honestly, Octavia's amazing, everybody knows her for more of her comedic stuff, and with The Help, she kind of showed a different side of her. But this, she is a very giving actress. As an actor, that's all you can really ask for -- somebody who is going to be there to give you what you need emotionally to get a better performance out of you. She's awesome, she's really good at it. When we were doing a lot of our heavy stuff, she's always saying something to break the tension or ease the mood up a little bit. She was definitely the veteran that you want to listen to and take advice from. She was very easy to talk to."

Octavia Spencer: "Ryan runs an amazing set, and he’s a very collaborative director. Ahna [O'Reilly] and I have known each other for years. We actually knew each other well before The Help, so she and I have been friends. And then Melonie is so amazing that it was a family unit to begin with, and we all just sort of acted as family. It’s very easy to love this group of people, though."

Ahna O'Reilly: "We hadn’t worked together since The Help and it was very wonderful, but kind of like The Help, she and I have no scenes together in this movie. She and I have been a part of four projects together."

Melonie Diaz: "Michael is like the glue. Michael and I had all our scenes together, so it’s kind of hard not to fall in love with him."

How was working with producer Forest Whitaker?

Michael B. Jordan: "We are a lot closer now than we were before, for sure. He was shooting The Butler so he wasn't around set as much as he would like, but he was always there to get on the phone and talk to me about some things. He didn't want me imitating anybody. He wanted me to represent Oscar for who he was and for what he represents."

Octavia Spencer: "Forest was actually shooting another film, but he was supportive and he called, and was like do you need anything. So, you just felt very protected going in. I love that while he shooting another project he was in touch with us. When you’re working on a shoe-string budget, you want your crew to know that you appreciate that they get up early every morning and stay late at night. Forest got the cast a coffee cart, doughnuts, pizza. It’s just kind of like, look we appreciate you. I was also too nervous to call him back at first, when he called me [about the film]. I was like, 'It’s Forest Whitaker I can’t call him back!' I had to work myself up to call him. It’s kind of crazy I know, but I’m still completely starstruck by the immense talent of Forest Whitaker. I’ve been a fan of his for years. The fact that he called me personally, you know, I’m not worthy!"

What lesson do you hope viewers learn from this film?

Michael B. Jordan: "I want people to leave the movie feeling upset, angry, and I want them to think. If I can have people leaving the theater and wanting to look at themselves in the mirror and think about how they treat people. Because honestly, Oscar was a human being, and usually when there's an incident with an officer shooting somebody or killing somebody, the media and other people going to trial they always tend to destroy the person's character, whether in a negative light or they want to bringing up every traffic ticket the kid ever got, or every class he ever skipped in school, they want to paint him be this monster. Or on the other end of the spectrum there are other people who want to paint him as this saint. And we want to just make him human. We wanted the humanity to come out in this movie. We want to get people to start treating other people with respect, no matter where you're from, no matter what your race or the social background, how much money you got -- start treating other people like people. That's one of the messages I'm trying to send out with the film."

Plus, see inside the Sundance Film Festival parties.

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