Rak Rakk

Two aliens run away from their planet Cubici to Earth in hopes that they won't have to work as much there as they do at home. They encounter several different characters, but don't quite know what to do with any of them and use Cubici-ian methods of communication that lead to fatal consequences. In addition, there is no "Rak-Rakk" on Earth, a substance that is vital for the aliens. How will the aliens deal with this?