Jamie Greenberg likes to think of movies as he would a longtime girlfriend. After all, he’s going to spend a lot of time with it.

“If I’m going to be dating a movie, it’d better be a movie I want to look at and think about a lot,” says Greenberg on the eve of the Slamdance premiere of his second feature “Future ’38.” Ultimately, that’s why the movie is so cartoony and fizzy and colorful. I just wanted more fun in my day.”

It’s a feeling that’s infectious, no doubt because Greenberg poured so much love over the past four years into “Future ’38,” which brilliantly blends the new and old into a time travel adventure where our heroes have no less a goal than stopping the rise of Nazism in Germany before it takes hold during the 1920s, only to do so requires a recipe for a formica isotope that only exists in the great unknown of 2018. Enter Mr. Essex (Nick Westrate), the Army’s top talent in 1918 who skips a century to retrieve the isotope, but Greenberg’s stroke of genius is to create a future more familiar to him than it will be to present day audiences, a 24-hour news cycle that actually requires a man riding a bicycle and video phones that require an operator to connect (played with zest by Sean Young). In order to make sense of it all, Essex quickly teams with Banky (Betty Gilpin), the spitfire owner of the hotel he stays at to help him along with his mission.

As rich and lively as the film’s color palette may be, the rat-a-tat repartee of “Future ’38” may outdo it as Westrate and a particularly radiant Gilpin trade pointed barbs and puns as if they were already in a verbal World War, with the film embracing its low-fi roots to play out like a real studio comedy from the 1940s on par with “The Thin Man” series where the theatricality of it is part of the great joy. Shortly before Greenberg headed to Slamdance, the writer/director who came up in the industry by crafting clues for the beloved “Where in the World is Carmen Santiago?” spoke about his latest adventure, the mischief involved in creating an alternate future and how the film achieved its distinctive visual look.

Nick Westrate and Betty Gilpin in "Future '38"How did this come about?

Why this particular story came about is that I wanted to do something that’s more me. This is my second feature and the other one [“Stags”] practically killed me. It was five or six years of my life and it was a brutal experience. It came out fine and people liked it — it was about these four 40-year-old guys who live in New York City, but someone said to me, “For your next one, you really ought to do something that’s more what’s inside your head rather than trying to be commercial.”

So the science fiction nerd in me made me want to do a time travel film because I always find that really fascinating and I thought if I’m going to make a movie about traveling to this wonderful, advanced, mystical future, that seems impossible because I know I’m not going to have the kind of budget to build elaborate exterior sets, technology and so on. But I always like to say we’re living in the future now — I mean, look at what our iPhones and GPS can do. Every day, every one of us is sending signals to a satellite up in space, so the thought that’s we’re living in “The Jetsons” already led me to think how do you highlight that in a fun way? Well, let’s take a look at it from a lighthearted 1930s perspective and look at what a crazy future world we live in. That opened more doors because that let me had tons of fun with that beautiful 1930s/1940s classic Hollywood screwball comedy aesthetic. I’m also an old movie nerd, so I watched a bunch of the old screwball comedies [such as] “Bringing Up Baby,” maybe 60 of them or 70 of them, and that really opened the movie into a whole other direction.

If you watch [the film], a lot of the focus is on this fun future idea of time travel, but part of it really also is the language and the incredible dynamic between the two lead actors, Nick Westrate and Betty Gilpin, so in a way, it simply became a period screwball comedy. Now, there’s whole chunks of the movie where we’re not really talking about technology anymore, particularly the latter portion of the movie when they’re in the German consulate – it really is like a 1930s screwball caper where they’re running away from the bad Germans, so what started out as a 1930s movie so as to justify making it a future movie turned into a love letter to these old screwball comedies and these great old films of the ‘30s and ‘40s.

How did you find Betty and Nick for this? They have a modern edge to them even as they able handle that kind of rat-a-tat style of the screwball films.

We just hit the lottery with both of them. I was the editor of the film as well, so I’ve really scrutinized every frame of this movie — at this point, I’m sure I’ve seen it hundreds of times — and I’m constantly thinking to myself, “There’s a moment where they saved my ass.” Nick seems like the worst secret agent ever in a charming way, and yet he’s the manly hero and there are moments where Betty’s character Banky just owns him and she’s just completely in charge, which I always love in a movie, too. Because the charm, the intelligence, the wit, and of course, I should say the skill that they bring to it, they just entrance the viewer and really cover a lot of little things. In terms of the budget, we were just scraping along, so their incredible performances really make the movie and all the more so when you realize the film was shot in 15 days. Strictly from a technical standpoint, because they had been able to master the dialogue the way they did, we could do these long takes in which they more or less never blew a line, that’s part of what got the movie made and that basically goes for the rest of the cast as well.

Betty Gilpin in "Future '38"This may be getting ahead of myself, but did you have to figure out how you were going to age the picture and the sound to look of the era it’s supposed to be made in? And did that affect how you shot the film?

Only to a certain extent. Alan McIntyre Smith, the director of photography, really wanted to shoot on the RED Dragon camera, which we did, [because] it gave us a lot of color depth. We knew the movie was going to be all about the color and we also knew that we would be heavily affecting the footage [in post-production]. This camera actually shoots in 6K, so there was tons of [visual] information and tons of color latitude, so that came into it, but beyond that, we didn’t need to get really specific. I actually have some experience doing some of these film aging processes from some short films that I’ve have done, so I had a general idea of what we would be doing that way.

It was actually what we did with the color that was the most ambitious. Like I said, the RED camera takes tons of color information, but the question is what you do with that. Our color grading process, which we did at ProMedia here in New York City, was very, very prolonged and very, very ambitious. If you saw the way we shot the footage compared to the way it looks in the final film, it’s amazing you’re able to alter footage that radically. What Alan shot was beautiful, but he shot it knowing that we then were going to be very heavily processing it. When I went back and looked at these 1930s Technicolor films, one of the things that really interests me is skin tones and facial detail because there’s something about people’s faces – Technicolor didn’t seem to handle light the way modern day color film does. If you look at skin tone from “The Wizard of Oz” and other movies at that time, there’s much less variation. A person’s face almost looks as if it was colored in with a uniform fleshtone color. So I went to our post-production people and said, “How can we do that?” How can you give me that? The color correction people at ProMedia really did figure out a way – they used tracking mattes, so in most scenes, we have a matte over the faces of the actors, and it travels around the actor’s face, so that [creates] a diffusion of color, all of which the viewer doesn’t know about. The viewer just knows it’s color and it definitely doesn’t look like modern color. It looks like 1930s color.

I wouldn’t want to spoil the great cameo that opens the film, but the introduction in general is quite fun. How’d you come up with it?

The script does not have that sequence actually — and that’s me narrating, by the way — but we added it after shooting the film. We figured for younger modern-day viewers, it might not be right at the front of their mind that 1938 was the year before World War II began and that Hitler’s aggression was already underway. Europe was in terror, but the United States was still sleeping on it because this was before Pearl Harbor and the military wasn’t ready, so we said, “What’s a quick way to get all of this out without having [the person in the cameo] say all that stuff?” And in a way you also would further establish in the viewer’s mind that the movie’s super vintage and old fashioned because no modern movie with a straight face would begin with a silhouette of a Walter Winchell radio announcer like that.

We shot it eight months after shooting the movie and we went to the home of our director of photography, we strung like a big backdrop and lit it and I got in front of the camera and that was that. That particular shot is inspired by an old movie about the FBI that begins [with] a narrator at a radio microphone in silhouette with a camera pushing in on him while he talks about bootleggers or prohibition that I happened to see that way after we made the movie and when the producers and I were talking about a nice way to establish the historical context right at the beginning, I said, “Hey, that’s doable.”

Were you actually able to film Sean Young’s scenes as the operator Mabel before shooting with the other actors so there could be that interaction on set?

No, funnily enough, we shot that after, too, so she never actually met the rest of the cast. Of course, that means when Nick Westrate and the other actors were talking to Mabel on the set, they were talking to a blank screen with none of that material filmed already. Watch the scene again and you’ll see Nick being so funny and charming and realize he’s talking to either me or the script supervisor mumbling the other character’s lines from off-camera, which makes his work all the more impressive. But then we went and shot Sean and we were able to time it properly, so it all gets edited together so they’re absolutely interacting with one another.

Given this was a low-budget production, what was it like to shoot those exteriors in the middle of New York City? Were you getting permits?

The subway stuff, we just went and did it and if anybody told us to stop, we would’ve stopped. The material that is actually dialogue out on the big street — the first scene when Banky takes Essex out into the real world and he’s saying, “Wow, stupendous! Look at the tall buildings” and they walk along and have a conversation — we actually permitted. New York is surprisingly easy and cheap, even for a small independent film to permit shooting an exterior, and if we had tried to steal that, that really would’ve been a problem for us because we had the camera on dolly tracks and a lot of people around.

With the one exception of Essex and Banky walking around Columbus Circle and then walking down into the subway, the exteriors are really all in Long Island City, of all places – I’ve seen the future and it’s Long Island City. [laughs] Who knew? The simple reason for that was that our studio was in Long Island City and we didn’t have time to devote a day or two to shooting off on location and having trucks and trailers, so my producers quite rightly told me the only way you can shoot anything outside is if it’s walking distance from our actual studio because we’re going to have to run back to the studio and shoot some more stuff there. The entrance to the consulate is actually the courthouse [there] at Court Square subway stop in Long Island City, and the stuff out on the street is right in front of the Citibank Headquarters at the same subway stop.

That process sounds an awful like the way they’d actually make movies in the 1930s studio system. Was this a situation where you were finding the limitations were making a more accurate film?

We were very lucky, though it was pretty strategic of me, because the movie, as you say purports to be a very stylized 1930s studio film, so the sets really could look like sets and the blocking of the actors [could be] pretty stagey [where] they were standing half-facing the camera when they’re supposed to be facing one another [because it] looks pretty accurate for a lovable 1930s/1940s film. Of course, that allowed us to shoot much quicker because the sets could be much smaller – sometimes a set could be a single wall instead of a big, pulled out three-wall set. For example, the scene between Essex and Banky when they go into the subway station, but before they get onto the actual subway, and Banky has hung her cosmetics mirror to do her makeup, not only was that not actually in the subway, but the backdrop for that is the width of the frame — basically, if you could see six inches to screen left or screen right, you’d see the back of the studio wall. It was like this tiny cardboard little flat that we put up, but it looks like a subway pillar covering frame left and frame right side of the wide shot that’s just a couple of little plaster things we threw up. So it gets you to be more creative and it’s also fun because you feel like, wow, we’re really pulling one over on the audience.

Some of the other little gags and stunts we [also] did in the old fashioned way, like the scene at the beginning of the movie when the scientist whips a baseball at Essex and he does this super-cool, one-handed catch looking in the other direction. Guess how we did that?

Did you remove some frames in editing?

We simply had him throw the ball, then we reversed the shot because if you throw a ball and it flies off the screen and I play it backwards, it looks like the ball is whipping perfectly into your hand. There’s also the scene where [Essex] throws two pencils up at the ceiling and the two balloons are at the top of the ceiling pop and land perfectly on his head. We had two deflated balloons sitting on his head with fishing wire and monofilament, which is more or less invisible, and there was somebody off-camera holding a fishing pole attached to the monofilament leading down to the balloons, so the guy just yanked the balloons up and when you play it backwards, it looks like the balloons land perfectly on the actor’s head.

After carrying this with you for so long, what’s it like to let it go now and send it into the world?

Well, you just said two different things. There’s the letting go and the putting it out into the world. Part B of your question, which is putting it out in the world and having people see it, I’m very neurotic about. I think it’s because I come from sketch comedy and improv comedy where you’re making up what you’re doing as you go along and you’re so attuned to whether people are laughing. I’m like a neurotic stage mother when my own movie is playing. I don’t like to be in the theater because no matter how much people laugh, it’s never going to be quite as much as I would want. And then you get into a really, really crazy thing I find where an audience will laugh at some jokes, but not others and I’ll find myself respecting their choices because they’ll go for the easier laugh. [laughs] But here’s an audience laughing at something I wrote myself and I’m looking down on them because of their choices! It’s a very bad instinct.

But the letting go part is fabulous. I’ve just been with this for so long and I’m delighted that it’s basically done. The work is not actually done because I’m promoting it, but the movie itself is done. You work on these movies for so long that my friends, who are not in the business, get used to me constantly saying, “I’m working on a movie” and I think everybody assumes there never actually will be a movie. [laughs] So it’s a little surreal and it’s a great feeling that it’s actually finally done.

“Future ’38” does not yet have U.S. distribution. It will play twice during the Slamdance Film Festival on January 24th at 9 pm and January 26th at 4 pm.