Dogtooth Tuna.
The fish is called as “Devil fish”, “Doggie”…anyway, people say them like, the most difficult fish to land. This is because they live in one of the most tough places in the sea and run so powerful like a cannonball once they’re hooked or shot.
So, the fish has been obsessing so many fishermen all around the world.
There is a young Japanese diver who’s been chasing this massive fish with just one breath and a primitive polespear, with his life.
His name is Kunpei KOSAKA. His dream is to land 100 kg+, which no one has ever reached before.
This is the ultimate challenge. It needs not only a great apnea capacity, but also all factors of underwater hunting.
Along the way, his passion became bigger and bigger, involving the people around him.
Our dream is to reach an unprecedented 100kg+ Dogtooth Tuna with a most primitive way, and to publish the whole story as a documentary film.
We named the film as “Mission 100” to express our passion.

“Blue Water Spearfishing”
Diving into the unknown ocean with just a single breath and targeting huge fish is always a deadly risky game.
In this sports, one tiny mistake can take your life.
There is a real about life, here

Dogtooth Tuna is a powerful, hard-fighting, the most difficult fish to land. So the fish has been obsessing so many fishermen and spearfishers all over the world.
100kg+ is exceptional and when it comes to 110kg+, it’s another level. Official record says no one has ever caught that size in the past 50 years.

That’s why I’ve been chasing a 110kg fish.

And I want to do it with the most primitive way.

In 2015, when Kunpei saw an old photo of a dogtooth tuna, everything has started.
At the time, he was an “Anker” so he afraid of the water, but the photo gave him a big dream.
He decided “someday”.
Soon after, the dream took him into a “Spearfishing Bum life”. He’s dove all over the country in search of the one fish. One time, he’d spent tough days as a commercial fisherman, and the other time, went foreign areas for months of freediving trainings.
He’d been chased the tails of tuna by himself.

At the end of 2020, he met two oceanmen when he visited the island in pursuit of Dogtooth Tuna.
Six years after chasing tuna, one man’s dream became three men’s “Mission 100”.
The circle widened further, and before long, it became the dream of six passionate oceanmen.

Although the crew members are at the mercy of the fast-changing dynamic ocean and the tough weather, they still keep challenging.
In 2021, after hundreds of failures, he finally set the new world record for polespear with 86.1 kg, which is the unbelievable record.

The next, 110 kg.



Kunpei is a first Japanese World Record Spearfisher. He spends 250 days of the year as a “Spearfishing Bum” life in chasing Dogtooth Tuna. AIDA Freediving Instructor. He can dive into 55m with Bi-fins, and hold his breath for 6’30 with one breath.

Director/ Cinematographer

Shintaro MURO

Persuiting the possibility of underwater filmmaking. In 2021, his short documentary won the “Sustainable Award 2021” in the Ministry of Agriculture, Forestry and Fisheries of the country. He is the organizer of AUKZEAL, and GREEN spearfishers.



Just pure passion for the ocean.

Photo-director/ Photographer


A underwater photographer who continues to express the connection between the sea and people. Since he was fascinated by freediving, he’s been diving all over the country for almost 20 years. He has a record of 70m as a competitive freediver. His representative works are “Water Being”, “PRESS”. Father of two pretty daughter.



He is a PADI professional diver and a photographer who has been chasing and capturing the breath of wildlife all around the world. He gained experience in underwater photography while working as a scuba diving guide in Thailand and Australia for years. His shooting style is both land and underwater, and his targets varies from large mammals to tiny crustacean.



“Hardvoiled adventurer”. ROC film. In January 2023, he will join the “Expedition to Pakistan” project to challenge the Karakoram, a high peak that has not ever been skied during the winter season. His representative work is “White Vibes”.


Koki Ohta

His Pure passion to explore the ocean lead him to wide variety of activities, from line-fishing to commercial spearfisher. The chief of GREEN spearfisher, a volunteer association to preserve local coast. His latest work is “No fish boy

The documentary film project “Mission100” has a financial issue.

Filming is taking place in remote areas and the weather is not stable.
The opportunities are quite few.
The expedition is a long duration, as it is a challenge against greatest nature.
In the past two years, we did 112 days of expedition, took almost 1000 dives,
then we successfully took 4 tunas, but our final goal “110kg” is still far ahead.

Currently, the expedition expenses are being paid by our own.
We are in a situation where it is difficult to continue the filming and future production.

If you share our dream, please join us in chasing this tremendous dream of the sea.

Sponsorship/ Gear supply
Ideas for collaborations

We are open to any kind of ideas!
We deeply look forward to hearing from you.

Click here to contact us.