SIMKIN: They say the first sound you hear is the beating of your mother’s heart – the original rhythm of life. A select band is trying to recreate that rhythm, pushing their bodies to breaking point and beyond in an incredibly arduous apprenticeship. They are Japan’s demon drummers.

The group is called “Kodo”, which means both heartbeat and children of the drum. Kodo is based on the remote, beautiful Sado Island, two and a half hours from Japan’s west coast. To become a professional demon drummer, you must endure two years of hell. The trainees live deep in the mountains. By the time I find them, the hour is late but it’s obvious this is the right place.

Over the course of a year, Foreign Correspondent followed the fortunes of several apprentices as they struggled through this backbreaking, heartbreaking journey.

SHOGO YOSHII: How much do we practice? Hmm, until I’m worn out.

SIMKIN: Shogo Yoshii quit university to devote himself to these taiko drums.

SHOGO YOSHII: One important objective is that none of us wants to be outdone by our mates, and each of us wants to become a drummer. That’s why everyone is a rival and everyone works hard.

SIMKIN: As the snow starts to melt and the blossoms begin to bloom, the new first years arrive and straight away they’re given a taste of what’s to come. They’re dumped at the bottom of the mountain and made to walk a kilometre to the top. They watch the second years practice with a mixture of awe and fear.

FIRST YEAR APPRENTICE: I feel very excited but I also feel like my personal fight - my personal challenge - is about to begin.

SIMKIN: The students’ first challenge is to carve their chopsticks and drumsticks, the pieces of wood that will sustain and rule their lives. Then it’s time for dinner and an opportunity to test the handiwork, but even this is a challenge. The students are forced to hold their chopsticks in their weaker hand – drummers need to be ambidextrous. Some struggle. They’ll go hungry until they master the art.

The students must grow and prepare their own food. The rice planting ceremony is a highlight, spirited yet solemn.

CHARLES KELLOGG: A lot of Japanese culture is rooted in rice culture so it’s really, it’s really difficult for us to understand where people are coming from, when you’ve never, for example, stepped into a rice field and actually done the work that normal people do.

SIMKIN: Charles Kellogg is one of the second years. He was born in Japan but grew up in the United States. The 26 year old came here against the wishes of his family, keen to rediscover the culture of his ancestors. The training school is part commune, part boot camp. The rules are strict, the lifestyle austere. There’s no television, radio, alcohol, sex or cigarettes for two years. Weekends off and holidays are rare and the students are paying nearly $10,000 a year for the privilege.

CHARLES KELLOGG: I think I define the importance of this experience for me with what I have to give up in order to attain it and basically I left behind my whole family and all my friends and people who can understand what I’m saying just to come here and study so it’s really important for me.

SIMKIN: In modern Japan, many ancient traditions are being put to the sword but the demon drummers are fighting to keep them alive.

They’re training to be drummers, but drumming is only part of the training. The recruits must learn traditional dance, the art of the tea ceremony, the rituals of Noh theatre. In many ways, this place is a microcosm of the idealised traditional Japanese society, where the group is more important than the individual – people working hard, working together, everything in harmony.

They are like samurai percussionists honing the mind and the muscles, dedicating themselves to their craft, pursuing perfection, ignoring pain and the pain is considerable.

It’s not just the drums that take a pounding, the students practice until they get blisters and continue training until the blisters get blisters. Their hands are red and wretched, but those who stop are left behind.

FEMALE STUDENT: When I was hitting today, I got blisters. The first two to three weeks I wanted to go home, but recently I’ve settled down and I’m happy that I came.

SIMKIN: They are woken, appropriately enough, by the clapping of two sticks. The students practice until late, get up before dawn and average just 5 hours sleep a night.

MALE STUDENT: Life is the most difficult part. Life is connected with training of course, but you never get any privacy and that continues from morning until you go to bed.

SIMKIN: Before class comes the daily run – 10 kilometres down and up the mountain. In summer, the temperatures soar, in winter they get below freezing.

FEMALE STUDENT: It’s a fight against myself. I think it’s particularly tough when I’m in bad health or when the weather is bad.

SIMKIN: This is what lies at the end of their two year journey – a chance to join the Kodo professionals. Taiko drumming first emerged in Japan more than 1,000 years ago. It was quite literally at the centre of village life – the boundaries of each town were defined by where the beat could be heard. Troupes like Kodo are a relatively recent phenomenon. I paid the professionals a visit at their village, on the far side of the island.

Yoshikazu Fujimoto is Kodo’s most senior member. He’s one of only three people allowed to play Kodo’s biggest drum.

YOSHIKAZU FUJIMOTO: In one sense, it’s like running five kilometres with all your strength. You put all your feelings, all your spirit into the drum with your whole body. You put your feelings into the drum sound.

SIMKIN: The drumming is vicious, visceral. Fujimoto performs for ten minutes, every blow powerful enough to rock the building and stir the soul.

By autumn, the first years have been training for six months and it’s time to show the outside world what they’ve learned. The demon drummers lead an anti-demon festival. They work their way around the island, stopping at each house, drumming to drive out the evil spirits. By nightfall, the dancers can no longer walk but still have to perform – possessed by Japan’s fighting spirit.

The night ends at a shrine on the top of the island. Eventually they collapse. Bodies limp, hearts beating a crazy rhythm, they’re carried into the shrine.

CHARLES KELLOGG: I’m sometimes amazed at how far I can go, especially with certain teachers, they just, they just push and it’s not like they hit you or they yell at you or anything, they’re just like, oh is that as far as you can go and then you have to, you have to find it within yourself and bring out everything you can and I think that’s, I think that’s really important and it’s really enriched my life.

SIMKIN: The night ends with an impromptu concert, an opportunity to thank the local community. Behind the scenes though it’s not all upbeat – there are hints about just how competitive Kodo is.

CHARLES KELLOGG: People are picked for particular parts and the most prestigious thing is to put on the demon mask. That was a little difficult for me because I was the only one who wasn’t chosen to put on a mask and I ended up being the lion, which theoretically is supposed to be more prestigious but kind of didn’t feel like that, yeah. Yeah and no one gets to see you when you’re in the big lion, yeah, yeah it is competitive.

SIMKIN: In winter, the classes move outdoors where the temperature is close to zero. Apparently crucifixion helps the first years learn about posture and pain. They have to stay like this for hours. Even by Kodo’s severe standards, this teacher has a reputation for cruelty. By the time they’re finally allowed to stand, few of them can. For some, it’s all too much. In the course of six months, three of the students quit.

Naoto Fukushima has thought about giving up – he’s here against his parents’ wishes but is desperate to graduate.

NAOTO FUKUSHIMA: It’s been my dream to join the drummers for two years now, and I think my dream is finally within reach.

SIMKIN: To fulfil their dreams, the drummers must pass a final test. Two years of practice and privation come down to a single performance. The students play as one, whilst knowing they’re competing against each other. Professional Kodo members cast a critical eye and make an unexpected decision. Normally, only one or two students are allowed to join Kodo, this year five are chosen. Another will become an administrator. Shogo Yoshi is one of the lucky ones.

SHOGO YOSHI: I’m not sure what made me stick it out but I have struggled through.

SIMKIN: Those who missed out must leave immediately. Charles Kellogg is going home to America without regrets.

CHARLES KELLOGG: Several times during the apprenticeship itself it was really hard to keep going and especially during the latter half of my second year. It was really kind of dangerous for a while but yeah I’m really glad that I came and it was a great experience.

SIMKIN: But Naoto Fukushima’s dreams are shattered. He’s become an outsider, isolated and lonely. The corridors and classrooms are silent now but it won’t last. Each year brings new recruits to the demon drummers – young men and women eager to live lives ruled by rhythm.