Beginning as a minor character, Kath was part of two major storylines.
During the plot to have terrorists break out prisoners Ros Coulson and Janet Dominquez, Kath is moved into a cell with Ros and helps her plot her escape. Kath tries to persuade Ros not to go through with it, though she is unsuccessful, the escape plan doesn't work anyway.
Kathleen is eventually released, but returns to Wentworth in episode 143 on a drunk and disorderly charge, but it is revealed that Kathleen was put inside by Tracey Morris' boyfriend Joe to make sure Tracy wont testify against him in court. Kathleen is eventually given orders to kill Tracy, but is unable to go through with it. She goes to Bea Smith for help, and Bea immediately shuts the steam press on her hands, putting her out of action, with an excuse not to carry out her orders.
Kathleen is sent to hospital to fix her burnt hands. Meanwhile Tracey Morris admits to Erica Davidson the real reason behind Kath's "accident". Kath returns from hospital and is not happy that Tracy has lagged about the incident.