Claustrophobic prisoner who first arrives at Wentworth in the same van as Barbara Fields, going so wild that she has to be sedated by Joan Ferguson after she kicks Sister Johnson. Later, she attacks Mouse from solitary when she tries to talk to her, and later Colleen Powell and Barbara when they bring in her lunch tray. However, she appears less a thug than a frightened woman very much on the edge of her nerves. When she is sent to a storeroom with Faye Quinn and the lights go out, she curls into a ball before recovering and attacking Faye. Joan suggests to Faye that she can use Paddy for protection against Bea Smith while running Joan's book. Because Bea is working so hard not to jeopardize her parole she has to go easy on Paddy when she stands up to her, but Paddy tells Faye that she would be on Bea's side anyway in a potential showdown between her and Joan. However, she continues to antagonize Bea by spilling detergent over her in an (unsuccessful) attempt to set her up for Joan.
It is revealed in that she has been imprisoned for attacking a man after being shut up with him in a storeroom at an office party. Dr. Weissman comes to visit Paddy and, despite her initial reluctance, he hypnotizes her into remembering exactly what happened at the party, as well as her mother shutting her up in the cupboard for hours on end during her childhood (hence her claustrophobia). Margo Gaffney tricks her into going into the rec. room store cupboard and locking her in, and after Joan has caught her attacking Margo, she lags on her (but appears to avoid Bea's wrath for this).
She manages a ride to Woodridge in a prison van for the concert, despite Margo's taunting, and there she meets Andy Hudson, whom she defends against other male prisoners (with very little gratitude from him!). In the same episode, she burns Lou (a Woodridge heavy) on the arm with an iron when he attacks her. Romance blossoms between Paddy and Andy, and she is forced to overcome her fear of dark, confined spaces long enough for a snogging session with him in a storeroom. Their session is interrupted when they have to rescue Chrissie Latham from Neil Murray, and Andy's state of undress gives away their romance, but Deputy Governor Carlson has a soft spot for Andy and turns a blind eye. Unfortunately, in they are discovered by the much less sympathetic Governor, and Paddy is taken to isolation until the women return to Wentworth.
Back at Wentworth, Paddy is now on Bea's side and helps Chrissie to restrain Bea from attacking Joan. When Andy's sister Kathy comes to visit, she passes a note to her from Andy which Joan notices. Later, to provoke Bea further, Joan performs an infamous body search on Paddy knowing she will find the note, and continues to do so even after Bea waves the note in her face. This leads to Paddy joining four other women – Margo, Chrissie and (I think) two unspecified background heavies – into a masked attack on Joan with baseball bats (how they smuggled them in remains a mystery). However, Joan manages to use Paddy as a shield to escape the attack. Again, Paddy has to restrain Bea from attacking Joan after yet another bout of ruthless verbal provocation. In the Great Wentworth fire, Paddy is trapped in the laundry with Mouse as the fire gradually engulfs the prison. Paddy is more industrious than the ill-fated Mouse and climbs through the air conditioning ducts to escape. She arrives at isolation, where Bea is preparing to die in the fire with Joan, but Paddy gets the keys and forces to Joan to help Bea so that they can all escape to the roof together. While recovering in hospital, Meg Morris tells Paddy she is free to leave the hospital (and Wentworth) after a favourable report from Dr. Weissman leads to the issue of her release papers. She goes to Driscoll House and tells Judy Bryant and Maxine Daniels about the fire. She visits Andy at Woodridge and tells Geoff Carlson that Andy's father has had a stroke. When he finds out he is upset that Paddy did not tell him when she had the chance. Andy is bashed by the male prisoners by sticking up for the female prisoners (temporary residents of Woodridge), and escapes the hospital to which he is taken so that he can do a job to help out his mother. However, when he visits Paddy at Driscoll House, Tony Berman shops him into the police, and both she and Andy are recaptured. Paddy is taken to Woodridge and says goodbye to Andy, who is being transferred to a prison farm.
Later on Paddy gets murdered by Nola Mckenzie by drowning her in a wash basin. Bea later revenges her death by branding a K for "Killer" with a soldering iron on Nolas breast .