“Saw”–a gruesome, tricky psycho-thriller about the two latest targets of a serial killer called Jigsaw, who devises complicated traps to torment his victims–is the brainchild of a couple of young Australian film-school graduates, writer-actor Leigh Whannell and director James Wan. The two met in class, and soon paired up to make a genre movie. “I came up with the initial premise and basically the whole set-up,” Wan said in a recent Dallas interview. “And I passed it on to Leigh, but Leigh wrote the script. We would brainstorm scenes back and forth, but I never actually touched the keyboard.” Whannell added: “We came up with these ideas together–we’re on the same wavelength–and then I’d go away and write, and show it to James, and because he’s going to direct it, that informs the writing.”

Whannell and Wan’s original intention was to shoot the film as an independently-funded project to serve as their introduction to the business. “We started the whole process wanting to make a film with our own money, ourselves–an independent film,” Whannell said. “And essentially if we had made that film in Australia, it would have been a really expensive business card.” But the two worked so intently on the script that it became something more. One element they struggled with was arranging the pieces so that it would successfully misdirect viewers. “It’s hard to fool the modern audience,” Wan said. “They’re so savvy and so subconsciously trained to spot red herrings. To out-think them is so hard. From our perspective, it’s how do we make a film that’s a puzzle without them being able to spot the answers? It’s all sleight of hand.” Another concern was to grab the audience’s attention with some especially memorable moment–in their case, a flashback to one of Jigsaw’s earlier traps, in which a woman was fitted with an iron jaw trap that could rip her face apart. “In the same way that Tarantino had that infamous ear-cutting scene in ‘Reservoir Dogs,’ that’s the one thing that everyone talks about,” Wan said. “You really need that kind of reaction.” Whannel added: “The irony is, we spent so much time on the script, trying to get it right, that people started taking an interest in it. And it kind of went away from being this thing that we were going to make in our back yards in Australia [to one] made in L.A. with Danny Glover and Cary Elwes. But I think our mutual desire to do it ourselves is what led to it being made–that confidence to say, this film’s going to be made, come hell or high water.”

The journey from script to movie was still difficult, though. Whannell and Wan shopped the screenplay among potential Australian backers, but couldn’t raise the funds. “No one said this was the worst thing they’d ever read–people really liked the script in Australia,” Wan said. “We just couldn’t raise the money. And it was a happy accident that we could [in America].” The key element was their decision to shoot a scene–the jaw-trap sequence, of course–to use as a calling card. “We picked one scene from the screenplay, and we shot it essentially to use that one scene to sell the script and ourselves as well,” Wan said. “That, and the script, helped us get the film off the ground.” Whannell added: “That was at the end of a long process of trying to make it in Australia. It wasn’t until we were going to come to America that we shot the scene. Making the short and going to L.A. was the last-ditch attempt at getting something happening with this film.”

That gambit worked, securing them modest backing and eventually attracting some real names to the project. Still, as Wan emphasized, “this is a really low-budget film. We could not afford even rehearsal time. A lot of time when we were doing rehearsals, we were filming…and a lot of times what got shot was the rehearsal. Personally I don’t think that’s fair to the actors, but it’s the reality of low-budget filmmaking like this. That’s why I have such a big problem when people compare [’Saw’] to ‘Se7en.’ I’m like, oh, God, David Fincher could put his actors [through] up to like thirty, forty takes and get it right. On a good day, I’ll allow my actors two takes. On a really, really good day I’ll allow them three takes.” The shift to an American setting also required Whannell to do some rewriting, excising the Down Under settings and dialect. But the surgery wasn’t that major, Whannell said: “It wasn’t like kangaroos were bouncing around or anything.” It was more of a challenge for him to suppress his Australian accent in his lead role as the younger of the two men trapped by Jigsaw. “Either James did a really good job policing [me] or I managed to stay on course,” he laughed.

“Saw” premiered at the Sundance Film Festival earlier this year to considerable buzz. “We finished it two days before it screened,” Wan recalled. Whannell said of the screening, “I just spent most of my time out in the foyer. About half an hour in, a woman came out and started putting on her coat. She doesn’t know who I am, so I asked, ‘Why are you leaving?’ And she’s like, ‘Oh, that’s way too intense for me, man,’ and I was like, oh, thank God. She could have said ‘I’m falling asleep.’ Thank God, someone’s leaving because they’re about to be sick!” Wan interrupted, “In Toronto, we actually had a puker!” And Whannell added with enthusiasm, “That was our finest moment.”

But the duo quickly added that their intention wasn’t to disgust people. When the script moved to California, Whannell said, “we didn’t tone it down–all that stuff remained in the script. But I think James did a good job of just hinting at it. The suggestion is powerful. I’ve watched ‘Saw’ a few times now, and I don’t think it’s that gory. I think the ideas are strong, [but] not what you actually see.” Wan added: “We want people to be disturbed, but we don’t want to offend people.”

So see “Saw” at your own risk.