They are all criminals who were miniaturized and banished to another world. They want to avenge themselves by proving that they can rise above their criminal ways and do good on Earth by helping the two human women who end up on their world.

They help one of them change her past so she never ends up getting in trouble with the law, and the other they use their technology to help her to go to different places and times on Earth and help people in need.

The civilization that spawned them sees them as incorrigible, so their best revenge is proving those people wrong by being better people.