CDUK was a one off project from J.P. Butterworth and K.R. Maars in 2006. Butterworth asked Maars to write some lyrics and he'd come up with a song and the result was the single "Her Brilliant Light".

Although the project was a one off the resulting song has since been performed by Maars' band Vampyrouss often with Butterworth as a guest.

The pair would also work together on another song "Eyes Like Autumn" which was eventually released by Vampyrouss on the 2013 "Evidence Of Evolution" EP

and a self titled single in 2018.