Cowan guest-starred in over 20 episodes of The Bill as Julie Saunders, the mother of the boy who accused PC Tony Stamp of sexual assault.
She also starred in "The Wench Is Dead", the penultimate episode of the Inspector Morse series, as Joanna Franks, a Victorian woman who is murdered on board a canal boat.
She played recurring characters Nicki in This Life (1997), Carla in Series 7 of The Queen's Nose, air stewardess Polly Arnold in the Channel 5 soap opera Family Affairs (2001), Tanya in Pulling (2003), and Chrissie Jackson in The Sarah Jane Adventures,[3] making her first appearance in the first episode "Invasion of the Bane" (2007).
It was a promotional video for Robbie Williams, directed by Jim Field Smith and featuring the song "Burslem Normals".
Cowan has also appeared in television adverts for Danone Actimel (2003 to 2004), Nationwide Building Society (2006), Cadbury (2007), and Cif cleaning products (2008)[5] She was a finalist in the So You Think You're Funny competition at the 1999 Edinburgh Festival Fringe.