Even sporting a few days worth of shadow, his sandy brown hair unkempt and wearing a wrinkled white tee shirt with peace signs scrawled on it with crayon in children's writing – the work of his own kids – Peter Sarsgaard still looks every bit the leading man. Since making his mark in the sinister role of murderer John Lotter in Kimberly Peirce's Boys Don't Cry and then countering it as a tragically pathetic dot com millionaire in The Center of the World, Sarsgaard has managed to keep Hollywood guessing for years. To this day, the choices have been divergent, playing Linda Lovelace's longtime tormentor Chuck Traynor in the recent biopic starring Amanda Seyfried and the bleak character of death row inmate Ray Seward on The Killing. His career in entertainment isn't the only facet of his life he keeps alternative. As a vegan and activist, his life in Brooklyn with wife Maggie Gyllenhaal is a stark contrast to the life of many of his contemporaries.

You've been a vegan for a while now. Has it become easier over the years?
Being honest, it's still really hard. On movie sets actually it's not that bad because there are a lot of vegans working in the entertainment industry. On the movie that I just wrapped I was actually wondering what the meat eating actors were doing!

How does it translate into your family life?
I'm a forager absolutely. I cook steaks for my kids all the time because that's what they like. I guess you could call my wife a pescatarian but my kids eat meat a couple times a week. They love it. My daughter happens to love bacon now because her grandmother cooked it for her once. Sometimes I feel like I'm in a bit of a laboratory in that right.

And you're a runner?
I have been for a long time. Even when I was drinking all the time, smoking and in the worst shape of my life I was always a runner. I run anywhere between 40 and 60 miles a week. I like to go midday, in the heat of the sun.

You travel for work, what are some of the great places that you got to run in?
When I filmed The Killing in Vancouver I loved to run in the mountains there. I lived right at the Seymour River, at the base of the Coast Mountain Range. There was always a great amount of wildlife that I would see. It was fantastic. I've run in Mumbai. It's amazing to go at 5:30 in the morning because during the day it's one of the most densely populated areas of the world but the streets are empty at that time. When I was shooting in New Orleans I would do my version of a pub-crawl and I would run in the intense heat from bar to bar getting drinks of water. I find that running through these cities and towns you can really see them in a more significant way than the usual tourist visit to Main Street.

You're also involved with a rock-climbing documentary in the works?
I'm starting to do the voice over. It's about the history of rock climbing at Yosemite. Back when it was a bit of a counter culture movement. They brought a surfer mentality to the experience where they would camp out at the base of mountain. It goes from that time in the sport to now when we have people like Alex Honnold free soloing. The film has a bit of Dogtown vibe.

Your brother-in-law Jake Gyllenhaal just wrapped Everest that filmed on location in the mountains. Have you chatted about that at all?
From what he has said of the trip it sounds like it was a very hard shoot. For me as an actor, there are some scripts that I'll read and think, "I'd love to see that movie." There on the location you're wrapped up in a down suit with just a little of your face showing. When I did Jarhead with him, we filmed for months and the action is amazing to watch when it's cut. But as an actor, the work can get mundane. For example, you'll actually spend a day just taking apart and putting back together a rifle.

Your wife is going to be on Sundance's The Honourable Woman, and you just came off your work on The Killing. Is the debate between film and television something that you've discussed?
I'm actually going to do another television gig this fall. It's called The Slap, and will be eight episodes. Jon Robin Baitz wrote it and Lisa Cholodenko is going to direct. It's going to be on NBC and it's great. I think if I'm going to do a movie that at all affects me as an artist I've just come to accept that I'm not going to make any money. There are still great movies being made and they can be made for less because of digital. But right now the other place to find great material is on television, as well as the best way to make a living.

What was it about this character that drew you to the project?
We know the whole arc. That's the nice situation with doing these eight episodes, versus doing something that might be open ended; you know where he is going to go. This character probably feels the most true to me than any other I've played before.

You recently wrapped Black Mass with Johnny Depp. How was that experience shooting in Massachusetts?
That movie was actor heaven. Johnny is awesome, and I loved working with him. There were a lot of people in that cast who very few studios would cast in a movie, but Scott [Cooper] is aware of them because he is an actor. He's an amazing director but sometime I think it's sad he's still not acting. I would show up and get to do a scene with Johnny and people like Bill Camp.

I saw some of the photos, that wardrobe looked like a delight to wear?
[Laughs] Listen, I look good in 70s clothing. Much better than I look in contemporary clothing to be honest.

If only we could go back.
I look at the leading actors from the time of Elliott Gould and think, "That could have been me." There was a different standard of physicality to Hollywood at that time. You look at the actors being cast now and there is a whole other level of athleticism to it.

Do you believe the influx of comic book movies has changed the public perception of what a hero should look like?
Yes. That's the new standard. I think that we'll look back at this time as an era in Hollywood. When the studios asked, "Can we wash clothing on your stomach?"