Kim evolved from an adulterous sister to a loving member of the Oakdale community. She first arrived in Oakdale for her sister Jennifer's wedding to Bob Hughes in late 1972, she fell in love with Bob as he also began to share feelings for Kim. Bob and Jennifer's marriage was at a strain due to the behavior of Jennifer's son Rick, Bob took a break to Florida and Kim who still had feelings for Bob followed him there and pretended that she had met him out of pure coincidence. Eventually Kim and Bob shared a one-night stand together and then the two returned to Oakdale where Jennifer announced she was pregnant with Bob's child. However Kim was also pregnant with Bob's child but she didn't want to hurt Jennifer so she married Bob's rival Dr. John Dixon. At this stage, show creator Irna Phillips planned to have Bob leave Jennifer for Kim, this caused outrage among viewers who thought Kim should've been "punished" for her adultery. CBS asked Irna to reconsider but Irna refused, they were forced to dismiss her as head Writer. At that time, the story had Kim gave birth to a stillborn baby.

Jennifer and Bob were happy until Jennifer discovered that she was dying of a rare disease of the central nervous system. Later it went into remission, but tragedy struck for Kim in 1975 when Jennifer died in a car accident. One day she had enough of John's controlling antics and ran out of the house. John followed but fell down the stairs. Kim then stayed with John out of guilt but she had started to fall in love with Dr. Dan Stewart. John faked his illness when he recovered and this forced Kim to leave him. Kim fled to a cabin and while writing a love letter to Dan a tornado struck and she sustained an injury that made her get amnesia. John then pretended to Kim that he had the perfect marriage with her. John made her contact with the outside world limited, thinking that her memory would return. When Kim did regain her memory she discovered she was pregnant with John's baby as he had taken advantage of her memory loss. Kim then left John to be with Dr. Dan Stewart.

Kim got together with Dan Stewart with resistance from his estranged wife Susan and married, in 1976, Kim gave birth to Andy Dixon and in 1978 married Dan. Tragedy struck in nearly 1979 for Kim when Dan was experiencing bad headaches and was diagnosed with a brain tumor. When Dan's illness grew worse, they went on vacation but were stumbled upon by Criminals Roy Barker and Chip Kelley who were robbing a store. The latter of the two was killed and Barker held them hostage, Dan disarmed him eventually and he was arrested, sadly the next day for Kim was even worse when Dan died. Kim found comfort in Oakdale's newest Business man, Nick Andropolous who was running a Greek restaurant in Oakdale. Kim reminded Nick of his dead wife, this was confirmed when his brother Steve arrived in town, he was shocked when he saw Kim who resembled his brother's dead wife. Kim and Nick then planned to get married but a Problem arose, Nick's dead wife Andrea wasn't dead, Andrea eventually allowed a divorce and Kim and Nick married. Kim's stepdaughter by Dan, Betsy was now seeing Steve who was a bad egg and was now involved in smuggling drugs. Betsy and Steve refused to see reason and ran away, Nick found them and threatened to kill Steve in furious anger, Nick made Betsy swear not to see Steve again which she did, then Nick sadly collapsed and died of a heart attack, leaving Kim a widow by three men, Jason Reynolds, Dan, and Nick.

Kim married Bob Hughes in 1985. Shortly after their wedding, she and Frannie were involved in a mystery which eventually revealed Douglas Cummings as Kim's admirer. Douglas kidnapped Kim and Frannie, and was ultimately murdered. Kim believed Frannie may have been responsible, and claimed she did it to protect Frannie (ultimately, Marsha Talbot was revealed as the killer).

In 1986, Kim birth to her and Bob's son, Christopher. Not long after, they heard from Frannie, who had seen a woman in the UK that looked like her. Kim, Bob and Frannie eventually learned that the woman, Sabrina Fullerton, was Bob and Kim's daughter. John Dixon and Memorial hospital staff had a role in taking Sabrina away as an infant and getting her out of the country. Sabrina tried to become part of the Hughes family, but stirred up conflict and came between Frannie and her then-boyfriend, Seth Snyder.

In 1997, Kim underwent a life-threatening heart valve replacement surgery, something sure to alter her and Bob's life for years. During this time she had an out of body experience where she would see her life if she had died on the operating table. In addition, Kim was injured in a church bombing and was in a coma for a time. She recovered with a new appreciation for her family and friends and a new commitment to make a difference in their lives. On this note, Kim donated her bone marrow to Hope Snyder. Kim was later shocked to learn that Hope was her very own granddaughter.

On filming her final episode in 2010, Hays said the last day was incredibly "poignant".
“The last day was poignant, and what was so incredible about it was how we shot pretty much in order that day. As each group finished with a scene, that would be the end of their involvement. But it wasn’t like tomorrow was another show, so the studio got really full. By the time they got to our scenes with Don and myself, there was hardly any room for cameras or the boom. In a way, it felt like being in a theater. We don’t normally have an audience. The stage manager asked if it was going to be a Problem for us, but we both said no. It was like everybody’s arm was around us. It was absolutely incredible, there was not a sound. It was like everyone was holding their breath. In a way, we were all doing it together. When we finished, Don and I both spoke a little bit to everybody, and the whole As the World Turns family moved to the other end of big studio where they had the world’s longest table set up, covered with champagne glasses."

Chris, now a young Doctor, fell in love with the teenaged Alison Stewart, Susan's youngest daughter. Kim didn't seem to have a Problem with the relationship until the couple decided to move in together—into the Hughes' home. However the relationship didn't workout, and after divorcing, Chris left Oakdale. Hays said during this storyline came one of her favourite scenes with Actress Marie Masters (Susan Stewart).
"When Chris married Alison. Marie and I had a scene where I went to her house, we were talking about our kids Chris and Ally. Kim was trying to make peace, trying to be reasonable, and Susan was having none of it. We got down to the floor and were getting ready to tape. In rehearsal, Marie had added a line at the end, “Be sure to say hello to Bob for me.” It was a real dig at Kim. At the end of rehearsal it made me so mad, as Kim. I knew what I felt like doing, and I didn’t do it at rehearsal. But I knew that if she said that during the taping that I would was going to let it fly. So we’re taping this thing, it had gone well. Kim was going to the door, and Susan said, “Be sure to hello to Bob for me.” I yelled, “Oh go to hell!” and slammed the door."

Hays said news of the cancellation of the show come as a shock to her. "It was the moment I realized that Kim wouldn’t be there anymore [tearful]. It was such a shock to me. It was just a shock to me."