Many rail-transit systems have Blue Lines, but only Boston’s ends at Wonderland.

“It’s too good to pass up, the Wonderland thing,” says Brad Anderson, director and co-writer of the new low-budget romantic comedy, Next Stop Wonderland. “Especially considering the fact that [Wonderland is] a skanky dog track.”

Anderson admits he and co-writer Lyn Vaus didn’t get to the track first. “There are a few movies I’ve seen that were shot in Boston Good Will Hunting included and all take advantage of the dog track.”

“It’s actually a rather nice, high-tech facility,” interjects Vaus.

“It’s not as skanky as we’d like it to be,” continues Anderson. “But it’s not actually thriving. Off-track betting. Nobody cares anymore to actually see the dogs run,” he huffs with feigned indignation.

Ex-Bostonians Anderson and Vaus are longtime friends; they worked together on Anderson’s debut feature, the barely released The Darien Gap, which Vaus characterizes as “a little edgier” than Wonderland. They amuse themselves by trading ironic rejoinders. Usually, it’s Vaus who makes the arch comment, though sometimes the two switch roles.

“The Blue Line seemed apropos, for the whole blue, melancholy, water motif running through the film,” offers Anderson. “It just seemed like a good backbone to build a story around.”

The Blue Line also goes to the New England Aquarium and to Logan Airport, two of the movie’s other principal locations. Unlike in Good Will Hunting, in which the protagonist, played by Matt Damon, always seems to have the Red Line to himself, Next Stop Wonderland’s trains are crowded. Of course, most of Good Will Hunting was shot in Toronto.

“The irony is that the Boston trains never really are that crowded. Particularly the Blue Line,” admits Anderson, a former Red Line regular who now lives in New York.

“It’s Matt Damon’s star power,” cracks Vaus. “He can’t coexist with commuters.”

If the Blue Line forms Wonderland’s spine, the aquarium is its heart. It’s there that the film’s heroine, played by Hope Davis, first doesn’t quite meet the male lead, played by Alan Gelfant. “I think we were the first feature film that shot there,” says Anderson. “They’d had some episodes of Spencer for Hire that shot there. They were very reluctant at first. But once we told them that it was sort of a pro-fish movie, they got on board.

“We actually wrote a big party scene to occur at the aquarium so we could make it into an actual event,” he notes. “The party scene in the film is a real benefit for the aquarium. You had to pay like $80 to come to it.”

Using the aquarium also gave Anderson and Vaus some exotic supporting characters. A subplot turns on the fate of a puffer fish, and one of the scenes features an important cameo by a rockhopper penguin. “We actually did have a penguin wrangler, who was quite good,” recalls Anderson. “But it took about 30, 35 takes before that penguin went the direction we wanted him to go.”

“We had a blowfish wrangler, too,” Vaus interrupts.

“It’s a stupid thing,” Anderson continues, “because in the movie we work with kids and animals. And they warn you, in film school even, stay away from kids and animals. And stupidly, we wrote both of them in.”

Wisely, however, when Anderson needed a shot of a breaching whale, he used stock footage.

Davis plays Erin, a recently dumped nurse whose mother places a personal ad for her; she skeptically investigates the responses. The film puts the ad in the Boston Herald, a working-class tabloid, but Anderson and Vaus placed their ad in the Boston Phoenix, the city’s equivalent of Washington City Paper, to sample the responses.

“We actually used the same kind of ad that was in the movie, to see what kind of response it would generate,” says Anderson. “We recorded the responses and used them to come up with ideas. Some very strange responses. Stuff no writer could come up with.”

“If you think any of those characters [in the film] are exaggerations, I would say that they’re not,” announces Vaus. “Brad has a recorded response to one of the ads that is far stranger than anything in the movie. When you see the movie, you think these people are representing themselves in such a strange manner. But that is how they choose to represent themselves, because they’re deeply insecure. They don’t know who they really are, or they’re afraid of revealing who they really are.

“I’m sure there are all kinds of wonderful people who make use of this service,” he adds. “But for dramatic purposes, we weren’t interested in them.”

Erin’s own motives, as well as the respondents’, are also on trial. When she tells one disappointed suitor that her mother wrote the ad, he asks for her mother’s number. Erin “is a very intelligent person, yet she’s engaged in this absurd thing,” Anderson notes. “And she knows that it’s absurd. That is a weak moment. It’s important to show that, because otherwise we’re putting her on a pedestal.”

“If she thinks this is just an experiment, she’s wrong,” says Vaus. “She is more invested in this than she’s willing to admit to herself, and that’s what that moment is supposed to point out. Although it’s probably just perceived as a joke,” he mock-snarls.

Erin’s mood and character are also established by the soundtrack, which is mostly sultry Brazilian jazz. “First and foremost, it’s just great music,” says Anderson. “And we wanted to break down the cliche of having a hip, MTV soundtrack. It’s a mood thing. The movie is many ways a mood piece, particularly her character. That melancholic quality, but there’s an energy to it as well.”

“It’s also very sensuous,” adds Vaus, “which gives a subtle eroticism to it.”

“I’ve never heard that before,” Anderson winces, affecting embarrassment.

Their banter apparently reflects the way the duo works. The co-writers believe in “keeping the process very spontaneous and improvisational,” Anderson explains. “So I know when we write a script and then we go into production, that at the end of the day the film will be every different from the script. It’s an organic process. Some directors like to be dictatorial; I prefer to be more laissez faire.”

“That’s not to say that the script wasn’t rigorously worked out,” Vaus cautions. “I look at it like jazz: If you’re going to improvise, you’d better know the tune. So we got people who knew the tune, and we got actors who were comfortable with improvising.”

“The script has to be there,” agrees Anderson, “but it has to be malleable. That comes when the actors start to embody the role. One of the reasons we wanted Hope Davis is that she not only embodied the character, but she was willing to imbue it with her own sensibility through the improvisation. Same with a lot of the other actors.”

Anderson studied at the London International Film School, where he got the chance to be an extra in Peter Greenaway’s The Cook, The Thief, His Wife, & Her Lover. (“The first NC-17 film, and I had a little part,” he boasts.) Then he worked as a film editor, notably on Washington filmmaker Haile Gerima’s Sankofa. For Wonderland, he says, his approach yielded 50 hours of film to be cut into the 94-minute movie.

“I edited it, as I knew I would,” says Anderson. “So it’s OK. I would never foist 50 hours of film on another editor. That would be immoral.”

Anderson also used to teach a course in “guerrilla filmmaking,” which he describes as “using mercenary, anything-goes tactics, anything to make a movie. The first movie we made together was made for 40, 50 grand. The way you make that movie is you gotta sneak onto locations, you gotta steal props and return them later. It’s using deception and military tactics.”

“You just go and do it until the cops show up,” injects Vaus.

“The great thing about that approach is that the energy of making the movie somehow gets translated into the film itself,” Anderson claims. “It energizes the process. Sometimes when everything’s taken care of, when you have big trailers and everyone’s staying in five-star hotels, there’s a certain complacency”

“I’m feeling it right now,” says Vaus. —Mark Jenkins