Part of the Circus Maximus film that accompanies the new Travis Scott album, it's also one of the most spectacular music videos of the year. Laura Serra Estorch, executive producer at CANADA in Barcelona, explains why recreating the Catalonian tradition of the Castellers for Sirens was "four weeks inside a production hurricane."

It is just one part of a much bigger project, one that involved some of the biggest (and notorious) names in international film - including Gaspar Noé, Nicolas Winding Refn and Harmony Korine. But the part of Circus Maximus - Travis Scott's 75-minute film accompanying his new album UTOPIA - that is devoted to his song Sirens is, by any stretch, a towering achievement. 

In fact one can justifiably say: quite literally a towering achievement. It's not that 'a cast of thousands' usually means exactly that, but in this case, it did take in the region of two thousand extras to bring Scott's vision for Sirens to life. And that vision was to create a human tower, reaching up to the sky.

Produced by CANADA in Barcelona, executive produced by Laura Serra Estorch and directed by Scott, the video recreates a remarkable tradition of the Castellers, that originates in the Catalonian region of Spain - where teams of hundreds of people combine to build human towers, and compete against other teams to see who can go highest.

Above: Laura Serra Estorch

I’d dare say it’s the biggest shoot we’ve ever done at CANADA.

As it takes many people - usually built around a whole community, including different generations - to create one of these towers, the video begins with hundreds of people running through the streets of Barcelona, before an even bigger group of people gather in a darkened space to begin the building process - with Travis Scott himself at the heart of it, as Castellers climb to create ever-higher levels, towards a light at the top of the space.

We spoke to Laura Serra Estorch, executive producer at CANADA, about making the Sirens video and discovered how her own personal experience of the Castellers gave her a head start in a hugely intense period of pre-production.

PROMONEWS: How did the project start for you?

LAURA SERRA ESTORCH: We were approached by Kathleen Heffernan, one of Circus Maximus’s executive producers, asking if we could make Travis’s idea for Sirens happen in a very short amount of time. I said 'yes'. And after that, it was four weeks inside a production hurricane.

Did the original concept come from Travis, or was this a collaboration between him and CANADA?

It came directly from Travis. He had a very clear idea of what he wanted in the video since the very first email. We received a written script for the entire Circus Maximus film, and our chapter specifically was quite detailed. 

He knew about human towers and about the Tarragona contest in particular, which is a contest that’s held once every two years, where all the Castellers teams gather together.

It happens in a stadium filled with over 15,000 people, every team wearing their own colour and several human towers being built simultaneously. It’s visually spectacular. Travis wanted to recreate it within a utopian world.

The Castells is a remarkable tradition in Catalonia, that started originally in Tarragona. Is there a personal connection to this tradition?

I used to be part of the Vilafranca team when I was 10. I didn’t last many years, as many people there do, but I was there long enough to understand the culture, to share their passion, and to be able to connect with them 25 years later to help make this project happen. It has been quite an emotional journey for me. 

Were Travis and his team aware of your personal connection to the Castellers when they originally approached you about the project?

I don't think they knew. They seemed very happy and relieved when I told them I had this connection and would do our best to make it happen. I heard they had a couple of "nos" before contacting us!

Where and when did you shoot the video? How many extras did you have?   

It was shot in Spain in early July over three shooting days. The first day was the biggest one in Tarragona, inside the Tarraco Arena, where the original Castellers contest is held. We had over 1,200 people involved, including castellers, extras and crew. I’d dare say it’s the biggest shoot day we’ve ever done at CANADA. 

The second day was in a Barcelona neighbourhood called Ciutat Meridiana. That’s where we had hundreds of people running through streets and over rooftops. Over 600 in total. 

On the last day, we shot in an apartment and a studio to cover all the corridors and interior shots. We had around 200 extras involved. 

The tower was the centrepiece of the video... and it is not something that can be repeated over and over.

Did you work with an existing Casteller team or club – or more than one?

We mostly worked with Castellers de Vilafranca, which is one of the main teams in Catalunya, both for the complexity of their towers but also because of the amount of people they gather in the team. They are the ones who built the big tower in the video and the ones who taught Travis the basics for him to be able to be in one.

We also had another four teams - Xiquets de Tarragona, Xiquets del Serrallo, Nois de la Torre and Castellers de Mediona - who were all crucial for Vilafranca to build a bigger tower on the day. The closeness, patience and hard work of all of them made it possible.

What were the big challenges in filming the making of the tower? Did you need to shoot it more than once? 

The biggest challenge was that the tower was the centrepiece of the video, and that is something that only lasts about 4-5 minutes from start to finish. And because of its difficulty, it is not something that can be repeated over and over until you get the right shot. It’s really a one-off. Hence the multiple camera teams, cranes and drones are located at every angle we could possibly imagine. 

We were lucky enough to be able to get two of them, though not a hundred per cent completed. You can imagine the tension around them, not only in the castellers but the entire crew. Then the “gralles” started to play, and it became a magic moment. 

How many camera teams did you have shooting simultaneously on the video?

We had three camera units working simultaneously on the first day with the castellers so we could ensure that we got all the necessary coverage in the very little time we had with the towers—and two camera units on days 2 and 3.  

Overall, it was a large crew for a music video, with over 200 people on day 1. We're incredibly grateful to every single one of them as it was a very tough day, even crazy at some points, but we managed to succeed as a team.

And how many cranes and drones did you have surrounding the tower at any one time?

We had two cranes, a Scorpio 45 and an E-Scorpion 45, a drone surrounding the tower, plus a third camera unit at the top of the stands.

Travis appears to be part of the tower - at different levels. Were you able to do this for real? How much training did he need to become part of the team?

Not 100% real of course, as being part of a 9-floor tower may take months, if not years of training. But I’d say we were able to do it more real and accurate than we first expected. 

We had planned for Travis to start at a lower ground first, having castellers climb on top of him, and then once he felt comfortable, maybe having him climb on top of a casteller. 

But when we came on set, he said he was happy to climb over someone straight away, and we went for it. He did a smaller tower that we combined into the big one; it made the VFX work much less complex than it could have been!

I’ve read that building human towers is not particularly dangerous – but it certainly looks it! Did you have any tower collapses – and any injuries?

It’s funny you say that because every time I talk to someone about castellers I keep repeating this same sentence, ‘It’s not as dangerous as it looks!’

Of course, it is not a joke, but when you see a collapse from the outside, it feels way more spectacular than it feels from the inside. There is some sort of cushioning in the way the towers fall that, most of the time, prevents people from serious injuries. 

We, fortunately, did not have any collapses nor injuries on the day; it all unfolded very smoothly on that front. During the build-up of the tower, the team’s coach is purely looking after its steadiness and making sure all is progressing safely. I was honestly so nervous that I can’t really remember how, but then I realised we managed to get very beautiful shots. 

• Laura Serra Estorch is executive producer at CANADA in Barcelona. More on CANADA here.