The backup crews on a 12-Meter are largely an unknown group.

She was held by an unknown group that released four videos of her.

The more recent kidnappings have been by previously unknown groups.

Or perhaps they had shared the struggle of performing in the same unknown group.

She is currently being pursued by an unknown group of women.

A small, unknown group of actors who work together in order to produce their own show.

Midway through the season, Michael is almost assassinated by an unknown group.

Some pinned suspicions on an unknown group looking for recognition.

It is not clear who was behind the attack (Though one unknown group has claimed responsibility), or what the motive were.

His brother was assassinated by a still unknown group.