''It's a timeless, romantic story,'' says Strange Fruit Manager on Tour Nami Hall, not mentioning at first that it's done 15 feet in the air. Two women and two men take to the heights on fiberglass poles to perform Swoon, which combines the elements of dance and circus during the 30-minute performance scheduled for Discovery Green. Above all, ''it's accessible,'' she says. At a recent performance, it wasn't just the audience who saw it. ''People in their offices working could see us blocks away,'' says Hall, who grew up in Portland, Oregon, and went on to graduate from circus school in Melbourne, Australia. They're hoping the same thing happens in Houston. The group has been performing since 1994, traveling all around the world.