The YouTube text says it all:
It's an harmonic occasion of quite a different kind when Carolina Eyck and Vinzenz Wieg make music together. With theremin, vocals, electric guitar and effects they are moving in the space between jazz, 20th century and modern classical music. Carolina and Vinzenz are creating stories and moods in playful interaction, never losing the grasp of each other. Flowing seamlessly from prepared compositions and free improvisation, their performances are brisk and nuanced without any safety net.
We had a long discussion in the forums about the role of theremins in jazz music. The duo of Carolina and Vinzenz are definitely pushing the envelope in this space, and to this listener, in a very impressive and exciting way! You can hear several more examples of the collaboration at Carolina's website.