Kristen Blake first came to Salem in 1993, and was saved from being mugged by John Black. Originally she was grateful, but when she learned who he was, she wanted nothing to do with him. She kept finding herself attracted to him, but her brother Peter constantly warned him to stay away from John Black. When a mysterious sniper began firing at John in Salem Place, he saved Kristen's life, and Kristen found it harder and harder to deny how she felt for him. Alice Horton decided to do a little match-making between the two of them, and put them in charge of the Horton Center together, then arranged for them to both be at the cabin, where they made love for the first time.
When John started looking into Kristen's past, he found a bloody wedding dress, and Kristen confessed that she was engaged to be married, but that they were lying low right now because someone tried to kill her husband-to-be at the wedding. Not only that, but Kristen had an even bigger secret...she was Stefano DiMera's ward, and she was hiding her 'father' who was dying of a brain tumor. When Stefano was kidnapped, she had to pay big money to get him back. John was horrified to learn she was Stefano's foster daughter, but still loved her. However, she swore to a dying Stefano that she would marry Tony, and she couldn't break her promise.
Kristen was all set to marry Tony when Marlena's daughter, Belle, disappeared (whom everyone thought was Roman's), and Kristen and John posed as husband and wife to get her back, horrified to learn that the woman trying to get rid of the baby was none other than teenager Sami Brady! This seemed to cement their relationship, and Stefano knew he had to break them apart. So he got his hands on Sami's diary, and the truth was revealed that it was John who actually fathered little Belle. Kristen went ahead with the wedding to Tony, but at the ceremony, John showed up, claiming he had proof that Stefano was involved in Curtis Reed's death. When it seemed Stefano died at John's hands, Kristen went through with the wedding to Tony.
In 1994, Kristen threw a charity event at Maison Blanche in her childhood home of Aremid. Kristen was shocked first to see a shackled John, and later to learn that Stefano was really alive and well. Tony ran back into Maison Blanche to get the laptop containing a file on John's past, and went blind as a result. So even though she was sleeping with John, she couldn't leave her blind husband. Later she learned that Tony switched her birth control pills with sugar pills, so she left him, and moved in with John. She was all prepared to marry John when they cracked the files on the computer, and learned that John was actually a priest! So Kristen, a strong Catholic, returned to Tony.
In 1995, Kristen worked with John (who was functioning as a priest) to save Marlena from satanic possession. After that, John arranged to be released from his vows, and Kristen then arranged to have her marriage to Tony annulled so that her marriage with John would be recognized by the Catholic church. Once together, Kristen learned that she needed to have a child quickly, as she had a medical condition which would soon render her infertile. She still planned to be happy with John, but when they all went to Aremid for Peter and Jennifer's wedding, Tony arranged to kill himself and have John blamed. John was arrested and, thanks to Peter, sentenced to death. Kristen couldn't help but wonder if, just maybe, John really did kill Tony, and at the trial, Peter forced her to admit that she believed John killed Tony.
Kristen convinced the Woman in White, whom they met in Aremid, to return to Salem with them, and Kristen, John, the woman, and Marlena all moved into the DiMera mansion. Kristen found a letter from John to Marlena, confessing his love, and hid it, terrified she would lose John. Marlena found the letter, but at that time, Kristen discovered she was pregnant. Marlena agreed to keep quiet because she knew that Kristen's pregnancy was very precarious, and moved out when John proposed to Kristen. Kristen was later shocked when, under hypnosis, John claimed that the Woman in White was really her mother, Rachel Blake. Rachel knew that Kristen had hid the letter, and begged her to confess. Under hypnosis a second time, Kristen asked John if he loved her or Marlena more, and he answered Marlena. When Stefano returned to town, she agreed to help him kidnap Marlena in the hopes of winning John back. This was the beginning of Kristen's decent into DiMera-ism, as in the beginning, she had been purely good.
When Rachel and Marlena flew to San Francisco so Rachel could have reconstructive surgery, Marlena made Kristen swear not to sleep with John or wear his ring. What Marlena didn't know is that Kristen had given Stefano all the flight information to kidnap Marlena. Stefano arranged for a double to be captured, and Stefano had kidnapped Marlena! After Stefano faked a crash, all were convinced he and Marlena were dead. Stefano supplied John with goggles that enabled him to see Marlena, and when she used the goggles, Kristen realized that Marlena was writing diary entries about her, and planned to destroy the goggles. Stefano planted a bomb to go off next time the goggles were used, which happened to catch John and Kristen. Luckily, they and the unborn child were fine, and John promised not to use the goggles again. When Rachel suggested that John and Kristen go to Paris (following the 'Queen of the Night' game), John left, and Kristen and Rachel soon followed when Stefano sent them a fax supposedly from John, asking them to come.
John realized Stefano was holding Marlena prisoner, and arranged a grand ball, but Stefano was one step ahead of him, and arranged for many women to be there, all of whom looked exactly like Marlena. However, Marlena and Kristen came face to face, and after a confrontation, Marlena ran to John. Stefano drugged John, though, and not only did he get Marlena back, but he managed to steal Marie Antoinette's crown as well. Kristen tried to find John to save him from Stefano, and an explosion down there resulted in the presumed deaths of both Stefano and Rachel. Later, at the hospital, Kristen lost her baby, but convinced the doctor to keep quiet, who got even with her by telling John that he and Kristen could not make love. Kristen and Peter used a hypnotic device to get John into Kristen's bed, but it was Marlena's name he called out.
Stefano appeared alive and well in Salem, and arranged to hire Susan Banks, a pregnant woman who bore an alarming resemblance to Kristen, to impersonate her when necessary, and Susan agreed to sell her baby to Kristen when it was born. Marlena became more and more suspicious that Kristen wasn't really pregnant, and talked to Laura about her suspicions. Later, Kristen was heart-broken when it seemed Peter had been murdered by Jack Deveraux. Kristen made the mistake of adjusting her pregnancy pad and being caught by Laura, but luckily, Peter and Stefano were on hand, and took her back to the mansion. Stefano wanted to take Laura out of the country, but Peter and Kristen convinced him to just wipe her memory clear for the last few days.
When Susan went into labor, Kristen was there disguised as a nurse so she could watch, but she got to see something else as well...John wanted to be married to the mother of his child before it was born, so Kristen had to sit and do nothing while John married Susan, whom he thought was Kristen. Susan handed over her son to Kristen, who was named John Black Jr., and left, but when she learned her baby had a heart defect, she returned, and asked for her baby back. Kristen convinced her that she and John would be the best parents for the child, but Susan began to lose it, and was convinced that she deserved to be John's wife and the full-time mother to her child. Susan threatened to expose Kristen, but Kristen told her that if she did, she would end up in jail, and John would always hate her. She did allow Susan to breast feed the baby (on doctor's orders), but when Susan started getting too close to the baby, she tried to get rid of her again. When John found the two women together, Kristen pretended she had hired Susan as the baby's nanny. Kristen asked Vivian and Ivan for help in locking Susan in a secret room, and when Marlena pieced the truth together, Kristen locked her in the secret room!
When Kristen learned that Laura had recovered her memory and was going to have Peter's coffin dug up to prove there was no body there, she made sure she got there first, and claimed that Peter had requested his body cremated. When Laura confronted Kristen, she broke down, thanks to drugs supplied by Kristen and Lynn Burke. When Susan began to worry about Marlena, Kristen told her that Stefano had kidnapped Marlena, and would do the same to her if she talked. Kristen stopped Susan from releasing Marlena by saying that John would hate them both and marry Marlena, so Susan began to impersonate Kristen in the role of John's wife, and locked both Kristen AND Marlena in the secret room. Kristen and Marlena were both forced to watch, and Kristen tried to dig her way out of the room to stop Susan and John's wedding, and ended up hitting a gas pipe, knocking out both her and Marlena. Luckily, they were rescued when Laura slapped Susan and knocked out the false teeth, prompting Susan to confess everything. Kristen and John were almost married when Marlena rushed in and told John about Kristen losing the baby and hiring Susan to impersonate her and give birth. Kristen then grabbed a gun and threatened to kill Marlena, but was stopped by John. Kristen was arrested, but soon released on bail.
Kristen crashed John and Marlena's engagement party at the Penthouse Grill, and became suicidal when she heard him propose to Marlena, but John managed to talk her down. Later, Kristen showed up at Marlena and John's wedding with Marlena's presumed dead ex-husband Roman. She convinced them Roman would be most comfortable in the mansion, and John and Kristen pretended to be married to allow Roman to think he had a chance with Marlena, whom he still loved. Later, Kristen and John went off to find the cure, meeting Dr. Rolf, who had the antidote. Unfortunately, the vial was broken, and John and Hope had to go off into the wilderness to get a new cure. Kristen and the others got back to Salem just in time to stop Marlena from marrying a dying Roman. But since any stress could kill Roman, John and Kristen had to continue to pretend they were married, and John moved back in with Kristen. When Roman saw problems between them, Kristen told him that another woman was trying to steal her man.
In 1997, Kristen answered the door at Jonesy's townhouse, and found Celeste there. In a battle, Kristen accidentally infected Celeste with the Jungle Madness disease. Stefano disowned her, and told her that when he got Elvis back (the name Susan had christened the baby with after getting him back, since she believed Elvis was his father...in reality it was Stefano in disguise) she wouldn't be allowed near him. This caused Kristen to go a little crazy, and Kristen tricked Susan into signing little Elvis over to her, but Stefano and John stole the baby back and returned her to Susan, who then impersonated Kristen at the courthouse (John delayed her) and said she wanted to return the baby to Susan. Kristen was furious, but couldn't do anything about it, as John and Marlena had already gotten Susan and Elvis out of the country. She got her revenge by telling Roman to go to the airport (knowing that John planned to propose to Marlena on his jet) so HE could propose to her, and discovered Marlena and John discussing how they were deceiving him. Kristen and Roman decided to fight for their loves, but when Roman learned that Kristen was now a liar and a schemer, he turned his back on her.
After Laura confronted Kristen in Salem Place about Peter, Kristen found Laura's Placiden, and used it to calm herself down. When Kristen broke into Marlena's penthouse, she found a fax Susan sent to Marlena, and she kidnapped Susan's sister, Sister Mary Moira, and told Susan to come to Salem, and bring the baby. Kristen drugged Susan, and was furious to learn that she hadn't brought the baby. She sold Susan into the harem for 'The Supreme Leader'. Susan had tipped Roman and Abe off ahead of time, and they were rushing to the airport to stop her when they got a report that Kristen had been found dead, so they believed the woman at the airport (Kristen) was actually Susan. They took her into the police station for questioning, where Susan's English boyfriend, Edmund Crumb, showed up. Thanks to him Kristen was released, and when Edmund proposed to 'Susan', Kristen accepted on her behalf, all the while terrified that if Susan was the dead woman, she would be charged with her murder. The coroner ruled the death a suicide (overdose), but Roman was convinced it was murder. When John found a suicide message from Kristen on the answering machine, he felt extremely guilty.
All of Salem turned up for Kristen's funeral, and Stefano had a heart attack after blaming the town for Kristen's death. After being released, he went to the cemetery and apologized for cutting Kristen out of little Elvis' life. Kristen, who was there, revealed herself to Stefano and begged him to help her get out of town, but he said it would look too suspicious. She was going to leave when Edmund brought both Elvis and his mother Violet to town. Kristen tried to drug Violet and sneak off with Elvis, but John found her and took her to the Penthouse Grill, where Edmund had arranged a surprise wedding. Kristen had to go through with it or risk exposure, and although she tried to escape Edmund, she couldn't and the two ended up on a honeymoon flight to Bermuda, after learning that Laura was arrested for Kristen's murder.
Before leaving, Kristen had left a note for Marlena from Susan, thanking her for all her help, including chocolates she knew Marlena liked, laced with penicillin, which Marlena was deathly allergic to. Belle was the one who ate them, but was saved by Roman. Meanwhile, on the plane, Edmund confessed that HE had killed Kristen, and rather than risk ending up dead if he found out who she was, she told him that when the plane landed, she was leaving, and he wasn't to follow. Once in Bermuda, Kristen and Edmund were surprised by Susan, who had escaped from the island and gotten to Bermuda with Violet's help. Susan exposed Kristen, and both Kristen and Edmund ended up wondering who actually died in the pool. Susan revealed that the dead body was actually a fourth Banks child, Penelope Kent (who had been given away as a child), who had come to Salem to help her, and told Edmund that it wasn't his fault, as Penelope was dying anyway. To pay Kristen back for everything she did, Susan arranged for Kristen to take her place on the island. When Susan learned what had almost happened to Belle, she sent a message to Kristen on the island telling her that John and Marlena were engaged to be married. Kristen wasn't heard from for years.
In October 2012, Stefano was on a mission to rebuild a broken DiMera family. Since Lexie's death, Chad and E.J.'s fight, none of the DiMeras were connected. So, Stefano reached out to Kristen to put the family back together. Because he had been sending her checks all the previous years, she agreed to help Stefano, knowing full well that her return to Salem would not be welcomed by everyone.
Kristen took the challenge on and met with both Marlena and John upon arriving in Salem. Neither were happy to see her, but Kristen insisted that she'd had a lot of therapy and was a changed woman. Marlena, especially, did not believe Kristen. Marlena was so sure that Kristen was manipulating them again that Marlena jumped to several false assumptions about several of Kristen's actions.
On the other hand, John was starting to believe that Kristen had changed and was making amends. This caused friction between John and Marlena -- which was Kristen's plan.
Kristen had her sights set on another Black besides John. Kristen and Brady began spending more time together. Brady began to fall for Kristen and she used this to her advantage. Kristen continued to let Brady believe that she had changed, all the while plotting to sleep with him as a way to hurt John and Marlena. When the two did start sleeping together, she encouraged Brady to keep it a secret. But, she was really plotting the best way to let the secret out.