This article originally appeared in Vulture.

You’ve probably surmised from the trailers that The Shallows gives you a hell of a battle between the bikini-clad Blake Lively and one royally pissed-off shark, but what isn’t clear until you see the movie is how much a third character comes to the fore … and it’s a bird buddy. There is no more important character in The Shallows—nay, there may be no more important character of the entire summer-movie season—than Steven Seagull, the charming, injured bird who hangs out on a rock with Lively’s imperiled Nancy and becomes the necessary Wilson to her Tom Hanks. The bird is a goddamn natural, nailing every single reaction shot as Lively natters on, and the rapport with his leading lady is a wonder to behold: This is the most chemistry Blake Lively has had with a co-star since she stared at pictures of herself in Age of Adaline. We simply had to call up The Shallows director Jaume Collet-Serra in order to get the scoop on the movie’s breakout star.

The thing I liked most about Steven Seagull is that he’s not a computer-generated effect. It’s clear that he’s a real seagull, and his bird quirks are what make him so endearing.

Exactly. When we started the project, this movie had so many big potential problems, like a CG shark, a difficult location, only one actor, and a lot of shooting on the water. The seagull kind of became a little problem, too, because a lot of people were saying, “What do you want to do about the seagull?” And I was like, “I don’t want to do a CG seagull because it’s going to be super expensive and it’s never going to look entirely right.” I didn’t want to do an animatronic, either, because I’ve worked with animatronics and if you get close to them with water, it’ll break them and it’ll look like shit. So I was like, “What about using a real seagull?” People were looking at me like I was insane.

What did they say?

“How are you going to get a real seagull to do what you want it to do?” And I thought about it. What did I really want the seagull to do? I just wanted the seagull to be a seagull. I actually didn’t want the seagull to do anything, other than what the seagull wants to do. If Blake interacts with the seagull and the seagull does nothing, well, that’s what the seagull chose to do. So it’s his choice. I give him freedom, or whatever.

How did you find the right seagull?

All we wanted was to find a seagull that was already injured on the right wing, so it couldn’t really fly away. We found many that had been in captivity that had been taken care of for years, and we found one specifically, this seagull named Sully, that was a genius seagull. I didn’t know it at the time that I was working with him, but he was kind of like the Marlon Brando of seagulls. He made very strong choices throughout the movie. He knew exactly when to react and when to look at the camera, instinctively. If we cut and had to reset, the seagull would reset by himself. He would go to first position. If the seagull saw Blake go back to her first position, the seagull would, too.

I. Love. This. Seagull.

That same feeling you had about the seagull, we all had. The whole crew fell in love with it. We were lucky enough to work with the seagull for many, many weeks.

So if I understand you correctly, the seagull had no prior training?

He’s not trained in the sense that you can say, “Do this” or “Do that.” But we built a little rock and the seagull was on that little rock, surrounded by water, for about three weeks before we started shooting. They would give him little cues, like, if food was put somewhere, he’d go to there. Just basic stuff in case we needed to direct him. But it was very minimal training, and we just needed the seagull to do whatever the seagull does.

In a film full of tension, the moment that was most suspenseful for me was when Nancy sends the seagull out floating on the surfboard. If the shark had eaten the seagull in that moment, I never would have forgiven you, Jaume.

I know, and that was never on the table. In fact, originally in that same shot, you’d see the shark fin.

And that was just too much?

It was actually too little! If I show you that scene with the fin and then nothing happens, it doesn’t work. You feel more anguish not seeing the fin. It’s better to see nothing. Your imagination is much more powerful than my fin.

There’s a great character beat where Nancy smashes a spider-crab on the rock and the seagull is clearly hungry for it. But she defiantly eats it herself … or tries to, before she pukes it up.

Blake and I talked a lot about that. You’re injured, and, yeah, it’s a cute seagull, but it’s just a seagull. You’re gonna take care of yourself first. You’re not going to become all Snow White all of a sudden and start being nice to birds—there’s a whole arc to their relationship. But obviously, Blake was very brave in trying to eat this real crab.

Ew, it was real?

Oh, yeah. They found some crabs that she could chew. The one that she smashes is CG, but the one she puts in her mouth is real. It was very brave of her to do that, but everything else that happens in that scene is unscripted.

A friend of mine came up with the theory that the seagull is some sort of guardian-angel representation of Nancy’s beloved dead mother. Did that cross your mind at all?

Not really, but I like the theory. It started more as a device for the writer. In the first script, she talked a lot more to the seagull, and we shot a lot more stuff where they talk. Finally, we just kept it more to a minimum. The audience was projecting more onto the seagull by showing less. Every time you see such a fragile animal, for people who have good in their heart, it’s human nature to feel for that animal. Sometimes, they may feel more for that animal than a human being!

What was it like the day you wrapped shooting on the seagull? I would think bittersweet, because there aren’t a lot of chances to make more movies with a seagull.

Oh, exactly. It was a big deal. A lot of applause and everything.

And the bird’s real name is Sully, right? “Steven Seagull” is just a character he plays?

Right, his name is Sully. It’s in the credits. She’s the one who calls him Steven Seagull, but if he could talk, he’d say, “Hey, my name is Sully.” [Laughs.]

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