Throughout the 1980s, alternative rock was mainly an underground phenomenon.

The song became an underground phenomenon, and charted on the Billboard Hot 100.

But in New York he is a strictly underground phenomenon.

How did it become this underground phenomenon?

It became an underground phenomenon - a portrait of the immediacy of a generation unable to deal with frustrations.

I'm kind of an underground phenomenon; the kids love me.

The novel has become a cult classic and became something of an underground phenomenon when published in Russia in 2004.

Black metal which had once been an extremely underground phenomenon in its early days became more well-known around the world.

Long considered an underground phenomenon, anime has been moving into the mainstream in recent years with the help of video games and fads like Pokémon.

Heavy metal remained, however, a largely underground phenomenon.