Karen Maguire (née Jackson) is the daughter of Sheila Jackson and her second husband, Eddie. She is married to Jamie Maguire, with who she has a son, Connor. Nigel and Delia Gallagher are her half-brother and sister.
During Series 1, she was the girlfriend of classmate Phillip Gallagher. Her family life was torn apart when she was caught by her father Eddie giving fellatio to Lip's brother Ian Gallagher in an experiment of Ian's sexuality. After much drama and smashing of windows, Eddie left the household and his family and never had contact with his daughter again, setting the stage for Frank Gallagher's relationship with Sheila.
After Frank moved in with Sheila, Karen experienced sexual tension with him, which blossomed into a full-blown secret relationship of which neither Sheila nor Lip were aware of. Karen became infatuated with Frank, even going so far as to dump Lip for him. However, Steve McBride overheard them having sex in the toilets at parents' evening and confronted Frank in disgust. Frank became scared and cut Karen off completely, leaving her distraught and emotional. Not long afterwards, Lip found out about Frank's affair with Karen and proceeded to violently beat him to a pulp outside of Karen's house. Karen suffered a breakdown from the chaos and left the Chatsworth Estate in disgrace to stay with her grandmother.
She eventually returned at Christmas 2004 and applied for a job at The Jockey. She pretended to be a lesbian in her job interview, which went down well with lesbian landlady Jez, who gave her the job and free accommodation instantly. Veronica was furious after finding out, as she stood to lose out on all the tips that her boyfriend Kev usually brought in. She also suspected Karen of flirting with Kev and proceeded to headbutt and punch her several times, getting herself repeatedly banned from The Jockey. However, Karen, wanting an end to the violence, proposed a plan which involved Jez walking into the toilets and catching Karen and Veronica kissing passionately. Not only did Karen and Veronica become friends again, but a shocked Jez unbanned Veronica from the pub due to her belief that she was a secret lesbian, but also warned Veronica to keep her hands off Karen in the future. This also cemented Karen's identity as a lesbian in Jez's eyes.
During her life at the pub, Karen became a close friend to fellow bartender Kev and regularly helped him with his illiteracy. She also became very distanced and alienated from her mother Sheila, through general lack of interest. She also treated her regular customer and old flame Frank with total contempt. Upon witnessing him about to cheat on Sheila with a brewery official, she threatened to wreck his life forever if he went ahead.
Jamie and Joe
Karen shed her previously slutty image in Series 4 when she met Jamie Maguire. Series 5 saw her becoming increasingly, albeit grudgingly more integrated with the Maguire Family and their somewhat violent way of life. Karen suffered a miscarriage early in Series 6. She also started an affair with Joe Pritchard, the boyfriend of her best friend and sister-in-law Mandy. Karen unexpectedly became pregnant, and had no idea who fathered her unborn child. In the same episode, in which her pregnancy was confirmed, Mandy died in an explosion, leaving Karen and Joe feeling guilty that she never knew of their betrayal. She decided to keep the baby, and raise it as Jamie's child. Her son Connor Joseph Maguire was born in the first episode of Series 7, and was delivered by Joe, who was possibly his father. Karen started to show signs of post-baby fatigue and her erratic behaviour worried the Maguire family. It was also implied that Joe had taken baby Connor on several occasions, to make it seem like Karen was a bad mother. It was later revealed that Karen was suffering from the depressive illness bipolar disorder, presumably inherited from her mother Sheila, who suffers from several mental health issues. Jamie, Mimi and Paddy all tried to support Karen through her health issues, but felt ashamed that one of their family members was suffering from such an affliction, seeing it as a weakness, so they covered up the fact when Karen is finally sectioned under the mental health act, opting to tell everybody that she was sent to prison for three months for assaulting brother-in-law Micky. When she was released from hospital, Karen's emotions were still erratic but she kept them under control with a course of antidepressant capsules.
Karen continued her sexual affair with Joe despite her recent nervous breakdown and she suddenly realised that she and Joe were deeply and, most importantly, mutually in love, and they concocted a plan to relocate with "their" son Connor. Karen was hesitant in separating from Jamie, in fear of the way he would react, his previous life of violent crime and murderous revenge never far from her mind. The affair was exposed however when Joe, grieving from the death of his father, realised that life is too short and casually confessed to Jamie, taking Karen away with him just minutes later. Karen decided that she wanted to go with Joe but that they must collect Connor before they leave, as they left him at The Jockey in the atmosphere of the revelation of the previous night. Karen and Joe stayed in his heavily and securely locked up shop in fear of Jamie's wrath. The Maguires refused to give Connor over to Karen and Joe so Jamie secretly passed him over to Kelly, who was working at the time at Lillian's Brothel. Joe made a deal with local gangster Roscoe, a rival of Paddy Maguire's, Roscoe got one of his cronies to reclaim Connor from Kelly, in exchange Joe told Roscoe the location of the Maguire brothers who previously robbed £150,000 from him in a botched exchange.
In the finale of Series 7, a still-unsure Karen was bullied by Joe into fleeing the Chatsworth Estate with him and baby Connor. Ian Gallagher stowed away in the car boot after seeing his friend Karen so unsure and not knowing what else to do. Joe revealed he had purchased a large, luxurious family home miles away from Chatsworth, where he, Karen and baby Connor were to live as a family. Karen confided in Joe her thoughts about being unsure about relocating with him, and she attempted to leave him, taking Connor with her. Joe was enraged by Karen's confession and viciously attacked her, prompting Karen to mention how his violence against Mandy had affected her. Joe pulled into a nearby lay-by and the two continued to argue, with Karen escaping the car with Joe in quick pursuit. The argument continued and escalated in Joe grabbing hold of Karen, and starting to throttle her violently. As Karen was about to pass out from lack of oxygen, Ian sneaked out of the car boot, and hit Joe over the head with a blunt instrument to save Karen. Ian delivered a second blow to Joe's head, killing him instantly. Ian kissed Karen on the cheek, and reassured her that he'd get rid of Joe's body. As Ian drove off into the distance with Joe's body in the car boot, Karen took baby Connor and headed back to the Chatsworth Estate, and to Jamie who she had realized she still loved.
In Series 8, Karen and Jamie went through marriage counselling, they were able to rebuild their marriage and Karen and Connor moved back into The Jockey. After a few understandably awkward problems they are now back to how things were before Karen's affair, happy.
In Series 9 Jamie began a surprise affair with Gloria Meak behind Karen's back. Karen remained completely unaware what was going on while Jamie and Gloria grew closer, with Gloria's brother Dom being the only other person aware of the affair.
In Series 10 however Karen began to suspect that Jamie was cheating on her and at first accused Ruby of being the other woman, much to Ruby's disgust. Karen expressed fear at not only the idea Jamie could be cheating but that it may not be true and her suspicions were being caused by her Bipolar disorder. Ruby assured Karen she would help and suggested they try a "honey trap" and try to tempt Jamie into cheating with an attractive woman. Logically the chose Gloria for the task, unaware that they had picked the very woman Jamie was cheating with. Gloria took some persuading but eventually agreed to help Karen but when she was meant to be seducing Jamie she warned him about what Karen was up to and then assured Karen that Jamie was faithful. The secret couple though themselves safe, but it didn't last.
Karen soon noticed Jamie and Gloria's behaviour around one another and went to extraordinary lengths to teach her husband a lesson. Jamie begins receiving threatening calls but is truly worried when a lock up of family business "product" is destroyed and all that is left behind is a slashed dress of Karen's. Things escalate quickly from there with Jamie receiving more calls and even a picture of himself with Connor that has the word "R.I.P" written across it.
- Rebecca Atkinson who plays Karen and Samantha Siddall who plays her on screen sister in-law Mandy are close friends in real life.
- Rebbeca Atkinson and Ben Batt who played Joe Pritchard are a couple.