How the Strays team got its dog stars to do R-rated acts on command: 'Humpity humpity'

Director Josh Greenbaum is breaking one of Hollywood's most famous rules: Never work with animals.

The director of Barb and Star Go to Vista del Mar returns with the raunchy Strays, a filthy canine comedy about a pack of decidedly R-rated dogs. Will Ferrell voices the scruffy and naive mutt Reggie, who sets out to find his way home, seeking revenge against his abusive owner Doug (Will Forte). Along the way, Reggie forms a pack of his own, including chaotic Boston terrier Bug (Jamie Foxx), smart Australian shepherd Maggie (Isla Fisher), and towering Great Dane Hunter (Randall Park).

Written by American Vandal's Dan Perrault, the film follows its four-legged leads as they embark on a sort of anti-Homeward Bound journey, cursing and humping their way across the countryside. (Reggie's goal? To find the cruel Doug and bite off a certain, um, R-rated appendage.)

Here, Greenbaum talks about working with animals and explains how he and his canine stars crafted the filthiest talking-animal movie ever.

ENTERTAINMENT WEEKLY: I heard you actually adopted one of the dogs who played young Reggie. Is that right?

JOSH GREENBAUM: It is! In the first minute or so, you see a little puppy in a cardboard box, and he needed a home after the film. I thought about it, and I called my wife. We had an older dog at the time, who's since passed on, but he held on through filming, which was amazing. But I called my wife and my twin daughters and said, "I might be bringing home a dog." Of course, they started screaming, and they've since named him Reggie. So yeah, I have Will Ferrell living with me in my house. [Laughs] I'm just hoping he doesn't ever want to enact revenge on me for any reason. If I come home one day and see him watching Strays, I will be very alarmed.

How was it working with a primarily canine cast? Who was the biggest diva on set?

No hesitation: It was Bennie, who plays Bug. Bug is this badass with Jamie Foxx's voice, who doesn't give a s---. He's supposed to be really rough and tough, but hilariously, the dog who played him was the most persnickety. If the temperature fell below, like, 72 degrees, he would shiver and need to be cuddled by his trainer. In his defense, I realized he does have short hair, but so did Hunter, who was never cold.

I'm not kidding you: We would bring in heaters and even a heating pad because he didn't like his paws on wet grass or wet cement. We had to hide this little heating pad that he could put his dainty paws on. We always laughed about it, like: "How did we get the softest dog, who's supposed to be the toughest dog?"

This movie is sort of the anti-Homeward Bound, and you poke fun at a lot of classic "dog movie" tropes. Was there a particular trope you wanted to subvert or have fun with?

We definitely got the ones that I knew we wanted. One of my favorites is the narrator dog. We called up Josh Gad, and I was like, "Either he's going to be offended that we're asking him to do this, or he's totally going to get it and jump in." Of course, he's such a funny guy, and he immediately got it. So, that was a great bit that I remember loving.

But it's not just the "dog movie" genre, but just dog behavior in general, right? I've had dogs my entire life, and I've always wondered why they do that spin before bed, and then they get up like that was the wrong position. Giving a voice to that felt very fun — particularly an R-rated voice. Not simply because you can swear, but if you're getting frustrated you can't find the right position to lay down in, you might be saying funny things. But what I wanted to film was something beyond a dog-spoof movie, something that holds up as its own thing.

What was the filming process like? Did you film the dogs first and then bring in the actors to record lines?

Yes, exactly. I recorded scratch audio, almost like a table read of the movie, just so I could hear it. I even built animatics to the scratch audio, which was just actor friends who came in and lent their voices to that process. And then, we went and shot. Originally, I thought I would play back the scenes for everyone on set, but I quickly realized that was not as helpful. It was a very weird set. Traditionally, you would have a rehearsal with actors and block the scene, but you can't do that. You can't ask these dogs, "Where would you want to say your line? When do you think you want to stand up and walk?"

So, I would take stuffed animals. I had four stuffed animals, and with my first AD, we would walk them around on set and show the crew what the scene was and what it was about. Then, we'd meet with the trainers about what behaviors we needed. Then, we would film. It wasn't until after that we started recording with Will, Jamie, Isla, and Randall. And that obviously brought the film to life.

I hadn't thought about that. You can't really rehearse with dog actors.

But I was so blown away by the performances — both the specific tricks that the trainers would give me but also the actual emotional performances they were able to pull out of those dogs. They showed me how they can train, like, seven different types of walks. You think, "Oh, it's just a walk," but if I'm a human, I can convey a ton with how I carry myself and the pace with which I walk. Am I going slowly? Am I nervous? Am I looking around? They would [train the dogs to] do that, to the point where you get these moments that feel so real.

There's almost no CG: 95 percent of the movie is all real dog performance, which was really important to me. I felt like the more real it feels, especially for adult audiences, the less you get pulled out — but also the funnier it becomes. There's moments where Reggie puts his head down and looks up because he's ashamed, and it's this really complex human emotion that we were able to convey through naturalistic dog behavior. If they're confused, I didn't want them to have to add furrowed brows with CG because I've never seen my dog do that when he's confused. [Laughs] So instead, you have them cock their heads, which is what dogs do when they're confused. I tried to lean on those naturalistic behaviors. It goes all the way back to Babe, which is a film I love. They really leaned on all the natural animal behaviors in that film, and I think it elevated it to go beyond a kid's movie.

That makes sense. Even with an outlandish premise, you want to root it in reality.

We also all live with dogs, so we know their behaviors. I was thinking about CG and the amazing work done on The Lion King or films like that. I can see a CG elephant and think, "Hey, that seems pretty good!" because I see an elephant one minute out of the year at the zoo, when I take my kids. [Laughs] But we really know dogs. We know their behaviors and their movements. That's part of why I wanted to make sure it felt very real.

There's one absolutely absurd scene where the four dogs hump lawn ornaments. How did you approach that?

I mean, there's multiple humping scenes. [Laughs] But that was an early moment of our shoot, where we literally had four dogs humping lawn ornaments. I think I yelled to the crew at one point, like, "Yes, this is really our job. We're really doing this, everyone." But that was another behavior where I said to the trainers, "Is this trainable?" They said yes, and they figured out their different techniques of how to do it.

At one point, it was 4 in the morning in Atlanta, with a lot of night shoots. Our set was quiet, and we were waiting for Bug to hump the pile of trash, when he is trying to convince these big dogs that he's crazy. You could just hear the trainer say a quiet "humpity humpity," which was the command the trainer decided to use as the word. Those are the moments where you realize what you're doing, and it seems so absurd. [Laughs]

But I also think the trainers were very excited. When we approached the training team, they were like, "We've been dying to do this." They've been doing kid's movies for 20 years, and they were all thinking, "How has no one done this before, a more adult and realistic version of what a dog's inner monologue might be?"

Is it true that the actor who played Reggie was actually a girl dog, which meant the visual effects team had to make certain adjustments to her, um, anatomy?

Yes, correct. [Laughs] Kudos to Sophie for being able to play the opposite sex. It makes her performance all the more impressive. But there are a couple scenes where Will Forte lifts her up. I had to talk to the incredible VFX team, who have done some of the greatest high-end movies in the world, and I'm describing how to make sure her testicles look accurate. [Laughs] You know, those very real conversations.

Did the actors record together, or were they mostly separate?

No, that was my whole thing: I kind of gently pushed-slash-insisted that they [record together]. Luckily, everybody was game (as seen in the exclusive preview above). Will and Jamie had never worked together, and they were huge fans of each other, so they were in every one of each other's sessions. We had a great script with great alt jokes, but I really encouraged them to improvise because they're Will Ferrell and Jamie Foxx. It would be foolish not to.

We would show them clips at times, as well. There's a moment where a leaf fell in the woods and it scared Bennie, the diva dog who plays Bug. We thought that was so funny: Bug is having this tough guy moment where he's like, "I'm not lonely! I'm not scared! Ah, what is that!?" And Jamie, of course, improvised that whole bit, like, "Ah! F--- you, leaf!" which was great.

Was there a particular scene or stunt that you were most proud of?

I mean, to be honest, it was almost every scene because any time we had four dogs, the odds of things going wrong just exponentially increased. That's the film. But the whole pound sequence was very scary because there's 40 dogs in that sequence. I wanted wide shots, too. A lot of these animal films, there's a reason why it's just single [shots] because it's much easier to shoot. But you would never do that if you were shooting a human, so I wanted to do moving masters and interesting blocking, which made the job of the trainers really difficult.

There's also a big climactic scene where Hunter knocks the door down. He was the least-trained of all the dogs. Three of the four dogs had zero training before we started prep, and Maggie was a trained Hollywood dog. But the dog playing Hunter, Dalin, was having a lot of trouble just sitting or staying. He would get the zoomies, which is when dogs just get excited and start running around. And he's a 150-pound dog with a cone, so he'd just smash around the set hitting equipment. I thought, "Well, there's no way he's ever going to be able to learn how to knock a door down. What am I thinking?"

But sure enough, full credit to the whole training team. Not only did Dalin get so much better through the shoot, but he loved to knock the door down. He was amazing at it.

So, he went from amateur actor to total professional.

Totally. Now, I'd hire him in a heartbeat!

Strays hits theaters August 18.

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