Behold the 'Vertical Pizza Box' by Pizza Hut, spotted on London's streets

Are you old enough to remember when Pizza Hut first made its mark in the UK? The American chain might as well have been a space rocket landing when it became a fixture of out-of-town leisure parks in the '90s, including at my local Festival Park in Stoke. It was an instant hit. All-you-can-eat buffets. Endless salad bowls. The collective challenge of eating your body weight in pizza, finished with a sprinkling of that mysterious crumbly topping.

Those heady days are long gone. The Festival Park restaurant closed last summer, marking the end of an era of birthday parties, Saturday dinners and slightly unhinged lunchtime indulgence. Alas, it's part of a much bigger story: the loss of market leadership, the pandemic hangover, and the UK dine-in franchisee entering administration, which led to the closure of around 68 restaurants and 11 delivery outlets.

Pizza Hut is still standing. But it's now operating in a far noisier, more competitive landscape. And that's where Iris comes in.

The agency's fresh, playful campaign aims to cut through by introducing a mysterious 'vertical pizza box' that has been spotted appearing on the streets of London. The stunt has prompted double takes, photos and plenty of online debate about how it could even work.

Rather than explaining the idea upfront, the campaign has been designed to live very much "in the wild". Random people have been seen carrying the vertical box across the capital, with early sightings shared by popular social accounts including the Archbishop of Banterbury and Food with ASB. The intention was simple. Let audiences spot it, share it and speculate, before Pizza Hut closes the loop on its own channels.

The thinking taps into Pizza Hut's long history of playful product innovation and iconic "firsts", from inventing the Stuffed Crust to famously sending a pizza into space. But this time, the focus isn't on proving what's possible; it's about reigniting curiosity around a brand that knows it has to fight harder for attention. It asks one simple question: if Pizza Hut has done it all… why hasn't anyone cracked a vertical pizza box?

Today, there are over 400 Pizza Hut restaurants across the UK. Globally, the brand remains vast, with thousands of locations backed by Yum! Brands and strong markets across Asia and the Middle East. It isn't going anywhere overnight.

But culturally, particularly in the UK and US, it's been overtaken. We may no longer default to dine-in pizza, and the world has changed dramatically since the '90s. Still, this campaign is a reminder of the affection many people have for a brand that helped define casual dining long before it became the norm.

"Pizza Hut has always had a history of doing things differently, and in the UK, we wanted to create something that felt genuinely surprising in culture," explains Roy Torres, Global Brand Creative Director at Pizza Hut. He believes the 'Vertical Pizza Box' is a fun way to spark conversation around the brand again, while celebrating "the innovation and imagination that sits at the heart of Pizza Hut".

"Working with Iris, we've created a campaign that's made for social, made to travel, and made to get everyone asking the same question: how does that even work?"

Menno Kluin, global chief creative officer at Iris Worldwide, says, "It's exactly the kind of idea we love making with Pizza Hut, simple, unexpected and designed for people to participate in. Instead of explaining the concept upfront, we put it out into the world and let the internet do what it does best: spot it, share it and debate it. It's a social-first stunt built to feel real, spark genuine curiosity, and turn a prototype into a talking point."

The campaign will run exclusively on social, with content designed to feel authentic, driving intrigue and shareability as the idea spreads. Later, Pizza Hut will close the loop by addressing speculation, confirming the 'Vertical Pizza Box' as a prototype concept and keeping the conversation open for future possibilities. In the meantime? I'll have a Hawaiian pizza and salad bowl, please.