Jason Guerrasio talks to director Lynn Shelton, actors Mark Duplass and Joshua Leonard along with the other members of the creative team behind this year's Sundance sensation, Humpday, about the collaborative process Shelton spearheaded to create this poignant comedy.

While on the set of her debut feature We Go Way Back, Lynn Shelton had an epiphany. Setting up a scene where the lead character Kate plays Pictionary with her younger self, Shelton decided to have her two actors sit down at a table and actually play the game. There would be no lines to memorize or marks to hit. She just wanted them to play while the camera rolled. And with what might have been simply a throwaway moment in her film, Shelton discovered how she wanted to make movies.

Four years later, her style of direction, which she's dubbed "upside-down" for its heavy contribution from the actors during story development and bare-bones production aesthetic, has been perfected with her latest film, Humpday (currently in select theaters through Magnolia Pictures). Featuring strong improvised dialogue and clever comedic beats, Shelton's story of two straight friends, Ben (Mark Duplass) and Andrew (Joshua Leonard), who after a drunken night of partying agree to film each other having sex and then submit the video to HUMP!, the popular amateur gay porn festival in Seattle, has gained praise this year from Sundance to Cannes. Some call it the indie contribution to the current Apatow-fueled bromance craze while others find it an emotionally truthful look at marriage and unfulfilled expectations. But for Shelton it's simply the culmination of years trying to capture truth and genuine human emotions on screen.

Like her methods, Shelton's foray into filmmaking has not been a traditional one. Growing up in Seattle, she wrote poetry, painted and enjoyed acting, and eventually received a BA at the University of Washington in Theater. She moved to New York City to pursue acting in the early '90s but quickly fell out of it and transferred to the School of Visual Arts. There she became drawn to B&W photography and, after taking a video workshop class on a whim, got hooked on the craft of the moving image. "When I started making films it was the extreme non-commercial end," she says in a phone interview from Seattle. "I had been doing this black-and-white street photography, almost Robert Frank style. Going into filmmaking I still wasn't thinking at all about the audience — it was pure expression." She supported herself as a freelance editor, taking on jobs cutting corporate commercials and short films while making her own experimental documentaries. Then in the late '90s she became pregnant and decided to move back to Seattle with her husband. "I immediately started getting jobs [in Seattle] as a narrative editor, and that's where I learned cinematic storytelling," she says. This led to her making the surrealistic black comedy We Go Way Back in 2005 for The Film Company, which chose her as one of four filmmakers to make their first slate of titles. (The company closed its doors within its first year). "It was an incredible opportunity," she recalls. "It was the first time I'd been on a film set. To that point I'd always done everything by myself or with one collaborator so the whole experience completely changed me. I had a really hard time with the traditional methods of filmmaking."

We Go Way Back would win the Grand Jury Prize at Slamdance in 2006 but for Shelton having a crew of between 30 to 50 people made the process stale and uninspiring. So her next film, My Effortless Brilliance, became an experiment in how to create a more naturalistic environment centered around the actors that would also keep her excited as a director. "I had a long list of items I wanted to try out," she recalls. "But one of the main things would be instead of trying to write a script and find people from a very large pool to fit that vision, to start with people you want to work with and then invite them to develop their own characters. Right from the beginning they'd know the characters and be able to figure out exactly what's going to happen in each scene. It was wonderful timing because around that time I also met Joe Swanberg."

Touring the regional festival circuit with his film LOL at the same time Shelton was on the road with We Go Way Back, Swanberg was becoming one of the main figures in the mumblecore movement with his intimate character studies of twentysomethings made on the cheap. After spending time with him, Shelton realized that Swanberg was already employing these same ideas about improvisation and collaboration in his films. "I would say he's been more of an inspiration to me than an influence," Shelton says. "When I talked to him I said to myself, 'I can do that.'"

With the confidence now to move forward on Brilliance, she reached out to Sean Nelson, the Seattle-based lead singer of the band Harvey Danger, to help develop the story. "I had seen brief, brief moments of him in his music videos and he just seemed really at ease in front of the camera," Shelton says. "He was a good acquaintance and when I described the idea to him of how I wanted to make the film he was all over it. From his enthusiasm and confidence I just had a feeling it would work out, though I'd never really seen him act." Through her talks with Nelson about his career as a musician and his brief taste of fame, the film became a story about a novelist who leaves his book tour in an attempt to rekindle a broken friendship. By the time My Effortless Brilliance began production over two weekends in early 2007, Shelton had stripped her crew down to five people, including a sound man, production designer, and an AC/P2 card wrangler/PA/grip. D.p. Benjamin Kasulke was the camera operator and Shelton, along with directing, produced and shot second unit. The shooting format changed from We Go Way Back's 35mm to HD (Panasonic HVX200). "Every single decision I made in terms of how to make Brilliance had nothing to do with making it cheaper [than We Go Way Back]," she says. "It was all about how can I put the actors at complete ease on set and make a film that felt real."

While in post on My Effortless Brilliance — and perhaps to distract herself from the editing process — Shelton began to look for collaborators for her third feature. Like Swanberg, Mark Duplass and his brother Jay were fixtures in the mumblecore movement. Their breakout film The Puffy Chair, which Mark also starred in, was celebrated for its mixture of goofy comedy and relationship drama as well as for its DIY aesthetic. Shelton admired the brothers' use of loose improvisation and she liked Mark's easy presence on camera. In August of 2007, Shelton signed on to be the still photographer for Craig Johnson's Seattle-shot True Adolescents, which starred Mark Duplass. "My secret ambition was to meet Mark, bond with him and hopefully find a collaborative partner," Shelton says. Her plan worked as the two instantly hit it off. "Creatively speaking we're kindred spirits in that we love the artistic process," says Duplass. "For True Adolescents I was encouraged to stay on script. Lynn had shot her first film on book and her second improvised so immediately we started talking about the plus and minuses of each [approach]. Within 24 hours [of meeting] we were both admitting we were missing the free form of improvisation and the gold that you get in the moment. We knew we were going to make something together."

Shelton finished My Effortless Brilliance, and it became a success, premiering at SXSW in 2008 and scoring attention for its bitter comedy and unaffected performances. With Duplass in mind, Shelton began thinking up ideas for her next project. Inspiration came when she attended HUMP! with Swanberg in October and witnessed his reaction to the event. "[Joe] had an interesting response to the gay porn," she remembers. "It just got me thinking about the relationship between gay and straight guys. Even if straight guys have gay friends and are fine with other people being gay there just seems to be this secret fear that there's some attraction towards each other." Shelton's original idea was that two friends — one a married, domesticated type, the other a single, charismatic adventurer — would attend HUMP! and realize that to live life to the fullest they would have to have sex with each other. Shelton wanted Duplass to play the loose cannon.

"I was in an airport when Lynn called me about this idea of two guys who get obsessed with HUMP!," Duplass recalls. "Having recently been married I believe when you're improvising you're deeply trying to connect to the character so I suggested I play the married guy, Ben." Shelton went with Duplass's instincts, but she had no idea who could play Andrew. Duplass had a suggestion.

Joshua Leonard is no stranger to the free-form style of filmmaking Shelton was determined to create. He starred in the landmark independent film, The Blair Witch Project, known for its loose story structure and improvisation, and for the last decade has lived in L.A. working in front of and behind the camera. During this time, Leonard admits he had "become pretty underwhelmed with acting in general." The actor and director knew Duplass from the festival circuit and remembers, "I was in New York doing some writing when I got an e-mail from Mark. It was one line that said, 'Do you want to play my best friend in a movie?' No other information, no director, no anything. And I responded 'Yes, absolutely.' He responds that it's being directed by this woman, Lynn Shelton, and it's about two straight guys who try to have sex. To which I responded, 'Okay, I'm in, but in the future please do not let me commit to a film without asking what it's about first.'"

All joking aside, Leonard was ecstatic to be invited into a process that might reinvigorate his desire to act. "I started out my film career working with friends and then took a more traditional approach to acting," he says. "I've come to an age now where I'm more interested in getting back to working with friends again, people who I trust."

Discussing their characters by trading phone calls, e-mails and a few iChats over five months, Shelton came down to L.A. for a long weekend in May 2008 to hammer out the story, staying in an apartment attached to the back of Duplass's house. Dubbed "The Summit" by Duplass, it was on this weekend that the three hashed out the whole film. "I had an initial treatment, so we had a base," says Shelton, "but we [needed to] come up with scenes and a specific backstory. How did these guys meet? What kind of experiences had they gone through? [We needed to find] things that would create little nagging resentments between them, which was great because that's where you really find the chemistry." The story evolved from Shelton's initial idea into one about two old friends who are conflicted with how their lives have turned out. Ben is reluctantly planning on becoming a father and Andrew feels he's a failure for not having created a landmark piece of art. When they hear about HUMP! they decide that two straight guys having sex is the ultimate art project and decide to make a porno and submit it. The three felt this was the most realistic story, which Duplass preached was paramount.

"For me, if you're going to improvise, if you're going to be loose, you better have a fucking bedrock story that's real or people are going to get bored," Duplass says. "I told them I was going to be beating the drum for realism in this movie because this concept could have turned into a farce really quickly. The goal was to actually make it conceivable that these guys would do this to the point that at least the audience could halfway put themselves in their shoes."

By the end of The Summit the three had developed the story, decided they would shoot the film in chronological order, and agreed not to flesh out the film's final act outside of knowing that Ben would reserve a room at a hotel for his porno shoot with Andrew. Duplass suggested that an unknown climax would keep cast and crew alike excited during the shoot while also forcing the acting in the scene to happen organically. "It was scary but it was cool," Leonard says of his reaction to the idea. "We would be so much in the world of those characters at that point that there wouldn't be any self-introspection or 'actor brain' going on — we would just be those characters in that room."

While developing the story with her actors, Shelton also spoke to her d.p., Benjamin Kasulke, about the film's look. Having shot all of her films, Kasulke is the closest observer of Shelton's evolution, and after Brilliance he was concerned that her drive for realism from her actors was causing the cinematography to take a backseat. "Technically a lot had fallen by the wayside, and I didn't think it was serving her work," he says. So Kasulke was adamant in preproduction about prelighting every scene and thinking out the look they wanted in advance. Shelton also knew from making Brilliance that the set for Humpday would run smoother with a little more help, so she beefed up the crew to 10 people. This would include a key grip and a dedicated digital-assets person. "In Brilliance our a.c. was also our digital-assets management person, and it just ran him ragged," says Kasulke, who again would shoot on the HVX200. "We didn't want to repeat that so we had someone who would be in charge of handling all of the P2 dumping, file imports into Final Cut Pro on set, and also be a go between from our editor, Nat Sanders, to myself and also between Nat to Lynn."

The final piece to the "upside-down" puzzle was editor Nat Sanders, who would be in charge of piecing the hours of improv footage into a story. Having edited everything she's ever made on her own, Shelton is the first to admit that letting someone else into the edit room was her most difficult adjustment. "It was hard in the beginning to restrain myself from grabbing Nat's keyboard while sitting with him," she says. Sanders had just come off editing Medicine for Melancholy when he met Shelton on the fest circuit. Editing reality TV to pay the bills, Sanders responded quickly to the idea of Shelton's collaborative project and promptly offered his services. "I e-mailed Lynn and told her I'd love to work on the project," he says. "She was flattered and said she wanted to work together but there was no money. I don't think she understood that I was offering to quit my job, sublet my place in L.A. and drive up there on my own." The film's small budget didn't allow for a proper editing room, so Sanders edited the film in Shelton's parents' basement. He began assembling after the second shooting day and says he was pretty much on his own to do the first cut. "It's really gratifying that you're given this sense of authorship on a film," Sanders says, looking back. But the real work would begin when Shelton joined him in the edit room.

Shot on a shoestring budget through fund-raising parties at her house, local grants, and locations from two friends who gave up their houses for the production, the 10-day shoot in Seattle last summer started slow out of the gate. "I think we just shot two scenes that [first] day," Shelton recalls. The opening scene of Ben and his wife Anna (played by Seattle actress Alycia Delmore) snuggling in bed would later be reshot, one of the few scenes that the actors would get a second try at. But Shelton says it didn't take long for everyone to get into a groove. The film's economical narrative structure minimized location moves by packing a lot into single scenes. Actors and crew had the time to work out a few different approaches to each scene without ever feeling they were losing the day. "Instead of having to shoot 200 scenes we only had around 20, so that gave us a lot of flexibility," says Shelton, who again shot second unit. Maximizing shooting time also gave Shelton the ability to get a lot of material for post. "Each take there's a lot of overwriting, and I just let [the actors] go to it to get them to that right place," she explains. "I'm just tracing on set to make sure I have all the ingredients for post. That drove the actors crazy — long after the scene ended I wouldn't yell cut, I'd just make them go and go because I do feel that sometimes those moments afterwards are the best ones."

For each scene Kasulke and his key grip prelit the room with 360 degree lighting so actors had free reign. He also used a lot of semitranslucent window treatments to develop the film's look. "We had ambient light coming from the outside and the best way to carve through that was with window treatments," he says. "I knew going in Lynn was making a sort of chamber drama. You had to address the fact that Ben and Anna are living in this home while also showing that there is a world outside. I felt like blown-out light coming through the windows would be a visual metaphor — this couple really learning to understand each other while in the background you'd see the world outside bleeding in."

The one scene Kasulke says was done on a slightly larger scale was the party scene where Ben and Andrew first talk about shooting the porno. With extras, a gaffer and three grips hired for the day, Shelton and Kasulke quickly had flashbacks of the We Go Way Back shoot. But there was an unconventional moment. In the scene where Ben calls Anna to let her know he and Andrew won't be home for dinner, Kasulke and Shelton were in the bathroom with Duplass as he made the call while a second until was with Delmore at the other house filming her reaction. Instead of just shooting one side of the conversation and synching their conversation later in post, Shelton thought the most authentic thing to do was have Duplass actually call Delmore and film her side simultaneously. "It was another instance where the production serves the needs of the actors," Kasulke says. "When you're watching the final cut you notice Mark is in a small bathroom. Lynn was standing just off camera next to me. As soon as we finished [each take], Mark would hang up and he and Lynn would talk, and I would take my cell phone and call where Alycia was and ask the second unit how it went. It was kind of a genius way to do the scene."

Most of the time Duplass, Leonard and Delmore nailed a scene in four takes. There were some scenes that were less developed in the script, so the actors would embellish them on the spot, like the scene where Andrew and Ben are complaining about their hangovers and Leonard surprises everyone by eating a spoonful of sugar. There were also scenes that were created on set, like Duplass coming up with a story that Ben would tell Andrew as they lay in his basement the night before they go to the hotel. "I told Lynn it would be funny to have a 'cut to' moment [in the film], where the guys have a heart-to-heart, a talk before the big event," says Duplass. "She said, 'Great, what would you talk about?' I told her not to worry about it, I had a story." He reveals a touchingly funny tale about once having an attraction to a male video-store clerk as a kid. "It's a third of something one of my friends told me, a third of my own personal experience and [a third] other stuff I rounded out to make it film-worthy."

Duplass says the respect everyone had for one another made it easy for anyone to voice their ideas and have them explored without others feeling threatened: "Nobody had anything to prove, so it made it easier to say, 'Your idea is better than mine, let's do it.'"

That camaraderie was needed when it came time to shoot the last scene, with actors and crew both filled with a mixture of excitement and anxiety of the unknown. Two rooms beside each other were reserved for the scene: one for the crew, the other for shooting. Having only seen photos of the room, Kasulke brought some China Balls, floor lamps and lightbulbs and hoped for the best. "The room was very beige and there was a lot of light in there already," he recalls. "But we were able to get this bloom feel which is not uncharted territory visually from the rest of the film. Once I noticed that I calmed down a little." Around 3:00 p.m. everyone checked in and Duplass and Leonard began to improv. "The first half hour take was freaking exciting," Shelton says. "I was holding one of the cameras and it was so hard not to be shaking up and down because it was so thrilling." Most of that footage is in the final cut. It includes some of the finale's golden moments, such as Andrew racing out of the bathroom and embracing Ben with a kiss followed with a disgusted look on both their faces when they part. That then leads to the two deciding to slow it down and just hug, which is Shelton's favorite scene. "I happened to have the angle, so my shot is in the film," she says. "I just noticed this funny posture of them pushing their bellies together but their crotches staying apart, so I started on their faces and panned down. I'm so proud every time I see it."

But adrenaline soon turned to exhaustion as 5 hours in the room turned to 8 and then 10 and then 12 (at one point Duplass says he'd gone delirious and kept repeating to everyone, "We're five minutes before the miracle! It's coming! It's coming, guys!"). They couldn't land the final shot. Sanders could see all this unfold when he reviewed the footage in the edit room. "They shot so many options," he says. "I think there were 13 different options to the ending of the movie. They didn't know what to do. You could see them getting more and more tired, I think there was one where Mark fell asleep in the middle of the take."

By the time the crew checked out of the hotel Duplass and Leonard were concerned they didn't get the ending and that Shelton would have to fly to L.A. to reshoot it. Says Shelton, however, "I knew we had something. I didn't want to tie things up too happily but I didn't want [the ending] to be a downer either." Sanders could see an ending in sight as well, though it wasn't the one Shelton had in mind. "I heard they didn't think they got the ending and they may have to do a pick up in L.A., so I knew that going into watching the footage," he says. "One ending, and the one Lynn was pretty confident we were going to use, had Andrew jumping on the bed euphorically after Ben leaves to cheer himself up. I looked at all [the takes] and there's this one where Josh calls room service to cancel the order they made and sits there looking sad. I think he felt like the take was over but Lynn didn't call 'cut.' So he sat there for another 5 to 10 seconds and realized he had to do something so he picks up the camera and looks at the footage. To me it was an incredible moment. I made that the last shot of the film. I was really nervous when I showed it to Lynn, but she really liked it and it became the ending."

Since receiving uproarious reactions at its Sundance premiere (where it was bought by Magnolia for a reported mid-six figures) and traveling to Cannes where it received its international premiere at the Directors' Fortnight, most involved reflect back on the making of Humpday as an experience that was extremely fulfilling yet would be hard to duplicate. "I think if we teamed up with the motivation of trying to repeat something it would be a huge failure," Leonard says. "This was the perfect [group of] people for the perfect project." However all of them do want to work together again, and they hope to incorporate aspects of what they did on Humpday in their own films. Some have already started: Leonard is writing and producing a film that Kasulke will shoot, and Sanders is talking with Shelton about editing her next film. But for Shelton, though she's come far with her "upside-down" method, she says there are still more experiments to be had. "My fantasy, and I hope to do this in my next film, is to shoot the entire film twice," she says. "Shoot in order and then shoot it again. With this style there's things that happen on set with the initial improvisation that you can never recapture because of the spontaneity, but there are other scenes that are so improvised that by doing them a second time they can be shaped a little better. That's my next evolution."