Catherine Tregenna

Catherine Tregenna is a Welsh television writer who has contributed to several Welsh- and English-language television programs. Though she sometimes partners with her brother, Jon Tregenna, she has been credited solely for her work on Torchwood. She is also the only writer to be nominated for a Hugo Award for her work on Torchwood.

Her scripts for the Doctor Who spin-off have all featured significant advancements in the emotional lives of the main characters. In particular, she is responsible for giving Owen Harper his first significant on-screen love affair (Out of Time), introducing Jack's brother (Adam) and his namesake (Captain Jack Harkness) and for revealing Torchwood 3 to Rhys Williams (Meat).

She later wrote the Doctor Who television story The Woman Who Lived.