Louise Bayliss
Louise "Lou" Bayliss was a research assistant with the Preternatural Research Bureau (PROBE), working alongside Liz Shaw. Bayliss' specialty seemed to have been office-based research and tea-making, while Shaw, more experienced with the unusual case subject-matter from her time with UNIT, carried out the on-the-scene investigations. She was unaware of Liz's old job at UNIT, being told it was "hush hush".(HOMEVID: The Zero Imperative)
It was during Liz's few weeks of compassionate leave following the death of her father that a change of the Minister in charge of PROBE resulted in a funding cut and the transfer of Bayliss to a different department, leaving Shaw as the only employee of the Bureau. (HOMEVID: The Devil of Winterborne)