Meet Mr Kinya Ueno, AKA Zim, the leader of one of Japan’s most curious subcultures.

They are Tokyo icons. Visit Yoyogi Park or the waterfront of Odaiba on a Saturday or Sunday and they’ll be there, rain or shine. Swivelling in leather get-ups to vintage rock blasted through portable sound systems, they’re Japan’s self-styled rockabillies.

Zim is the leader of Black Shadow, a well-known gang who dress up like 1950s rock’n’rollers. During the week, Zim is Mr Kinya Ueno and he holds down a regular nine-to-five job. But he prefers not to talk about his life Monday to Friday, for he is a man who is truly working for the weekend.

Black Shadow’s heyday was in the 1980s, when Japan experienced a retro-rock boom and American and British pop culture offered an irresistible lure of freedom to rebellious Japanese youths, who railed against a conservative society ruled by the proverb “the nail that sticks out gets hammered down”.

Zim left high school in the provinces as soon as he could and fled to Tokyo as a teenager, determined to become part of the scene. Like many who reject Japan’s corporate treadmill, his decision consigned him to a life on the margins.

But for a member of Black Shadow, being part of the gang was more than ample reward. Music and fashion provided more of a satisfying life than being one of Japan’s corporate salaryman drones ever could.

Heavily tattooed, clad in black leathers and with their “Regent” pompadour hairstyles blow-dried and styled to crazy heights, Black Shadows do what many Japanese can only dream of: express themselves. Extravagantly. Unabashedly.

Now these rock’n’rollers are growing old. Zim, now 45, has been in the gang for nearly 30 years. But teens today are into J-pop or electronic dance music. They have home-grown styles such as cosplay (dressing up in anime/ manga/ cartoon costumes) and don’t look to the West as much as Zim’s generation once did.

Still, as long as Zim can wax his Regent and shake his hips to the rock’n’roll beat, he’ll keep coming back each weekend to the place – and the people – that gave him his identity and set him apart from the mainstream; that made him and all the Black Shadows, in a word, different.