Maureen Tudor was an ordinary mother swept into madness when her daughter Rachel became a heroin addict. Her family slowly fell apart as a result, hastened when her daughter died from a heroin overdose at the age of 18. Broken by the loss of her daughter, Maureen succumbed to madness, focusing her rage on the man she thought responsible. Paddy Maguire was the drug dealer who indirectly supplied her daughter and Maureen saw him as her target for revenge. The actions she took in seeking revenge make her the main antagonist of series 6.
Though she usually appeared quite composed, Maureen would have sudden mood swings. While holding Paddy hostage, she would often fly into rages for various reasons, including Paddy swearing and his flippant attitude. She had a boyfriend at the time of kidnapping Paddy, he spoke to Paddy briefly early on, revealing that he was against Maureen kidnapping him but neither helped nor hindered her in any way. Her boyfriend then left her over the event.
Maureen continued her every day life during the course of holding Paddy hostage, so it can be assumed that she was capable of hiding her madness from the outside world. She also mentioned working as a nurse when first injecting Paddy with heroin and is seen working as a nurse when Paddy discovers her by chance at the hospital.
In Series 6 Maureen began meeting Paddy at the cemetery, Paddy visiting the grave of his son Fergal and Maureen her daughter's. It is unclear if Maureen began waiting for Paddy at the cemetery with revenge in mind from the beginning, or the more likely, noticed him there one day and slowly started to think up her plan. She befriended him first until one day, she and Paddy had a drink together, whether she drugged him or just got him considerably drunk is unknown. Maureen tied Paddy to a bed and over the course of a few days revealed who she was and what she was doing.
She soon revealed her true plan, she began injecting Paddy with heroin over the course of a few days. Quickly getting him addicted like her daughter. She then released him to struggle with his new forced addiction, something that slowly destroyed his life.
Before such events however Paddy hid his addiction as well as the events with Maureen a secret from those closest to him. But his habit and the events eventually came to light. Paddy spent a long time searching for Maureen, to exact his revenge but when he did finally discover her, by chance at the hospital where she worked he followed her home. She expected him to kill her and was ready to die but after experiencing heroin addiction for himself he understood her, and apologised.
Surprisingly Paddy and Mauren then had a drink together, talking of Rachel and events. They were getting on perfectly until Maureen let slip that the last time she saw her daughter, she slammed the door in her face. She felt she needed to show her daughter that she was serious, and that she couldn't bring the chaos of drug addiction back into her life. Realizing that Maureen turned her daughter away when she came for help, just before her death, Paddy left Maureen in her kitchen.
Perhaps admitting her own hand in Rachel's death to herself, Maureen decided to kill herself. But not content to just take her own life she wanted Paddy to feel exactly what she went through. She phoned The Jockey, asking for Mandy and told her that she had found a wallet with nothing but £300 and a raffle ticket from The Jockey in it, asking Mandy if she could come pick it up. Thinking it was her lucky day, Mandy went to Maureen's house. It was then that Maureen revealed who she was, saying that she wanted to put an end to everything that had happened. Excusing herself under the pretence of checking if the kettle had boiled she left Mandy to break the gas main, attempting to light a match Maureen was dived on by Mandy and a scuffle ensued.
Paddy, hearing about how a woman had phoned and asked specifically for Mandy, realized what was happening and he and Micky raced to Maureen's. Hearing her father at the door Mandy left Maureen bleeding on the floor and made a run for it, but Maureen managed to light a match just as Micky pressed the door bell causing a second spark. The house exploded, killing Maureen and Mandy Maguire on the night of her engagement party.
Paddy eventually broke his addiction and left the Chatsworth Estate for good, leaving his family and now ex-wife behind. He picked up the pieces of his life but Maureen's actions directly contributed to the break down of his marriage, the loss of his daughter and the strained relationship with his other children.