This article covers a subject that is part of the real world, and thus should not be taken as a part of the Holby universe.
HolbyBlue is a police drama that aired from 2007 to 2008 in the UK. It consists of 2 series. It is a spin-off show of Casualty and Holby City, and is set in the same fictional town of Holby.
Casualty character Charlie Fairhead, portrayed by Derek Thompson, made a guest appearance in the show. In addition to this, Chloe Howman starred in the series as PC Kelly Cooper, and later went on to portray Rita Freeman on Casualty from 2013 to 2016.