After Expo 2025: Yoichi Ochiai’s null² Evolves into null²ⁿ in Yokohama—Our Visit

At Expo 2025 Osaka, Kansai, the signature pavilion null² (Null Null), produced by Yoichi Ochiai, became a major talking point.

After the Expo closed, it returned in a new form in Yokohama as null²ⁿ (Null Null Nexus).

Inside null²ⁿ (Null Null Nexus)!

It opened on October 14, 2026, on the fifth floor of Yokohama Landmark Plaza!
At the Osaka–Kansai Expo, its mysterious mirrorlike exterior and conversations with AI-powered digital humans attracted attention as experiences unlike anything before.

Now null²ⁿ carries that vision into a more advanced, permanent museum theater.
Visitors explore five areas, including two LED theaters, for immersive experiences combining mirrors, light, sound, and digital technology.

We visited null²ⁿ in person!
How does it differ from the Expo pavilion, and what surprises are hidden inside?
Here is our firsthand report.

An entrance to another dimension

Immediately after entering, you put shoe covers over your shoes!
If you visited null² at the Osaka–Kansai Expo, you may remember having to remove your shoes before entering—and perhaps even feel nostalgic.

The first space you encounter uses the same material as the exterior membrane of the Expo’s null² pavilion.

That unforgettable, unusual material has made its way to Yokohama.

You can now step inside an environment that recalls the unsettling deep bass you heard when passing the pavilion for the first time.

Ochiai described this area as a transition from ordinary reality into another dimension.
From here, there are experiences for your ears and body as well as your eyes. Past Expo visitors may feel a sense of familiarity right from the entrance.

The Expo mirror theater evolves in Yokohama!

If you are amazed already, save some excitement!

The next room is where things really begin.
Here is Room One.

This is an evolved Yokohama version of the Osaka–Kansai Expo’s mirror theater.
Some people will be thrilled to enter again, others delighted finally to get their chance, and first-timers may feel bewildered. The scenery is astonishing in different ways to each visitor.
There is one thing you should definitely do before entering.

Prepare the official Mirrored Body app before your visit!

For a deeper null²ⁿ experience, we recommend downloading the official Mirrored Body app in advance.
If you used it at null² before, you can continue using the same app.
Be sure to update it beforehand, as a new update has been released.
New features, including a stamp rally, give you more to explore.

The app lets you create a digital counterpart of yourself by registering your knowledge, voice, and appearance.

Registering and logging in before arrival enables it to connect with the on-site experience for greater immersion.

Those who spoke with a digital human at the Expo may be especially curious about this feature!
At the media preview, the Mirrored Bodies of Yoichi Ochiai and Myaku-Myaku took part.

Watching Myaku-Myaku and Ochiai wander about right in front of us was so charming and funny that I nearly laughed during filming.

Here you can converse with a digital-human version of yourself and experience artificial life and a variety of scenes created by AI and humans.

One major change from the Osaka–Kansai Expo is the addition of a fifth LED surface!
According to Ochiai, this is a significant evolution, making the space larger than the Expo’s mirror theater.

If you visited the original theater, come experience the changes for yourself.
This part takes approximately 10 minutes.

No visuals at all: a space experienced through sound and bodily sensation

Next is Room Two, a unique space with no visual video presentation whatsoever.

Instead of watching images, you listen to sound and experience the sensation of your body existing in different places.

I knew that was the concept, but nobody told me it would be pitch-black!
It is so dark that visitors are asked not even to light up their phone screens.

Would we hear music, or the sounds of different landscapes?

It reminded me a little of the Jellyfish Pavilion at the Osaka–Kansai Expo, but here a different mysterious world unfolds solely through hearing.
This is a completely different approach from familiar projection mapping or immersive attractions.

The contrast with the dazzling scenery of the previous room is so sharp it can be hard to keep up.

Here, instead of relying on sight, you perceive the world through sound and bodily sensation.
Experience it for yourself and consider what Ochiai hopes visitors will feel.
This room also lasts around 10 minutes.

You cannot discover every hidden detail in one visit

Next is Room Three.

Cameras, tools, and other objects people have used over time line the space.

Depending on your generation, you may discover something wonderfully nostalgic and revisit old memories.
It is also fun to explain to younger visitors the objects that once felt indispensable in everyday life.

I could not count all the different objects on display, but some make sounds.
Look carefully and you may find others beginning to move.
They do not move continuously.

Which items move, how do they move, where do the sounds come from, and what appears on the monitors and televisions?

You cannot possibly catch everything in one visit.
Although you spend roughly 10 minutes in this room, finding every object that moves at certain moments is difficult.

Ochiai explained that the space invites us to consider what human “symbols” are.

We use everyday tools without giving them much thought, but what meanings do they hold, and what relationships have people formed with them?
It is not simply a display: movement and effects prompt deeper reflection.

It resembles Room One—but is it really the same?

This room looks quite like Room One, yet something about it feels different.
It is a mirror room visualizing the process by which AI perceives the world.
You can experience the sensation of drifting through a dream.

It feels like an expression of what takes place inside computers and AI systems.
How does AI learn, and how does a computer perceive the world?

The entire space makes these invisible processes tangible.
Countless lights, discordant sounds that resonate through your body, and uncertainty about where you are—reality or a dream—draw you into an indescribable world known as the Forest of Null.

Ochiai says the point is less to understand a spoken explanation than to reconsider the relationship between humans and computation through your senses.
The room reportedly also contains interactive effects that respond to visitor movement.
Those sensitive to flashing lights, rapid movements, or sudden loud noises may want to take care.
This room lasts approximately 10 minutes too.

There are surprises that make you want to return!

From the final room, you can take a long look at Room Three from outside.
But that is not all.

Many mechanisms are hidden here. Some can only be understood after discovering clues in this final room—even if you noticed something strange during your first visit. It is cleverly designed to reward a return trip.
Explaining more would spoil the surprises, so see them for yourself.

Plenty of appealing merchandise

You can purchase null²ⁿ merchandise here, including T-shirts and socks like those Ochiai wore at an earlier press event.

And if you missed out on null² merchandise!
A selection of items from the original null² is also available here.
There are five varieties of each pin badge, making a complete set particularly striking!

From Expo 2025 to Yokohama and GREEN×EXPO 2027

Yoichi Ochiai’s null series connects Expo 2025 Osaka, Kansai, Yokohama in 2026, and GREEN×EXPO in 2027.

2025: null² (Null Null)
A signature pavilion at Expo 2025 Osaka, Kansai, known for its mirrorlike exterior and technology-driven experience.

2026: null²ⁿ (Null Null Nexus)
The permanent museum theater at Yokohama Landmark Plaza featured in this report.
It develops the Expo experience further.

2027:null⁴ (Tetra Null)
A pavilion planned for GREEN×EXPO 2027, with an exterior inspired by a mirrored life-form.
It is exciting to see how experiences born at the Expo continue into the future in new forms.

null²ⁿ hours, ticket prices, and access

null²ⁿ (Null Null Nexus) opened on October 14, 2026, on the fifth floor of Yokohama Landmark Plaza as a permanent museum theater.
Planned hours are 9:30 a.m.–9:00 p.m., with a visit lasting approximately 60 minutes. An attendant guides visitors through five immersive areas.
Tickets (tax included) cost ¥3,900 on weekdays and ¥4,500 on weekends and public holidays for visitors aged 13 and over. For children aged 4–12, tickets are ¥3,000 on weekdays and ¥4,000 on weekends and public holidays.
One child aged 3 or under is admitted free per paying adult.

Tickets are reserved in advance for a specified date and time; same-day tickets are available only if spaces remain.
The venue is about a three-minute walk from Minatomirai Station on the Minatomirai Line, or five minutes from JR Sakuragicho Station.
Many people were unable to reserve null² at the Osaka–Kansai Expo and missed the experience.
In Yokohama, you can spend about 60 minutes in its evolved world.

null⁴ (TetraNull) Exhibit and Experience: Four Giant Mirrored Forms Rotate Like Prayer WheelsPublished: 2026.08.03

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