The youngest of Bea Reardon’s children, Chelsea Reardon was a singer and came to Springfield, in late 1986 with her fiancé Jean-Claude Lavale, ostensibly to visit her sister, Maureen. While driving to town, Jean-Claude suddenly became unconscious and he and Chelsea got in an accident with another car. Jean-Claude died due to crash-related injuries, and Chelsea sued new doctor, Rick Bauer (Maureen’s stepson!) for malpractice. Though family and friends tried to talk her out of it, Chelsea didn't drop the suit until Rick's cousin, Johnny Bauer, learned that Jean-Claude was a diabetic and thus may be fallen unconscious behind the wheel. In addition to singing at local clubs around town, Chelsea became Phillip Spaulding's assistant in 1987. Phillip, at the time, was a columnist at his father, Alan Spaulding's newspaper, the Mirror, and began a series of investigative pieces on the stolen-art syndicate. As a warning, Paul Valere, the head of the smuggling operation, had Phillip's apartment ransacked, prompting Chelsea to destroy his expose in order to protect him. Phillip rewrote the piece in a blander version, only to have the original turn up and make the front page! Alan told Paul not to hurt Phillip, so instead, Paul tried to ice Chelsea by rigging a microphone to electrocute her. Luckily Jackson Freemont saved her in the nick of time and began developing feelings for Chelsea when Phillip didn't seem to be returning her affections. However, at some point during this investigation, all that changed and she and Phillip became lovers.
Meanwhile, Chelsea learned that Alan was also involved in the black art market but told only Maureen since she feared bad blood between father and son. However, Phillip finally learned about that and forgave Chelsea. When Chelsea and Jackson discovered that Warren Andrews had killed Paul Valère, Warren kidnapped them and Alan, but luckily Phillip saved them while Warren was arrested. Chelsea then quit as Phillip's assistant and began to work for Alan at Spaulding though she and Phillip remained as lovers. There was just one problem. Phillip was still obsessed with the apparently deceased Beth Raines and that made Chelsea rather frustrated. At this time, Jackson, seeing both Chelsea's singing talent and beauty, became her business manager and began to vie with Phillip for her affections. When Chelsea realized that they were fighting an old rivalry for Beth rather than a rivalry for her, she lost interest in both men. Phillip wrote her a letter telling her his true feelings for her, but Jackson intercepted it. When Chelsea found out about the letter, she and Phillip got back together and they became engaged in 1988. Unfortunately, at this time Phillip was obsessed with wresting power away from Alan while Chelsea wanted to reunite them. Finally, when Chelsea found out about Phillip's plans and wanted to warn Alan, Phillip locked her up in the Towers. Disgusted, Chelsea bitterly broke up with Phillip.
Not long after, Chelsea found love with Johnny. Chelsea and Johnny had a wonderful relationship and, in 1989. they began to work for Holly Lindsey at WSPR. Johnny was the host of a talk show "One on One' while Chelsea was the producer. At the same time that Chelsea started to react jealously to Holly's flirtations with Johnny, she was pleased to learn that her college roommate, Rae Rooney was coming to town. When Johnny and Chelsea became engaged before Christmas, Chelsea began singing on Johnny's show. Holly was surprised how many people called in to WSPR and approved of the pairing of Johnny and Chelsea, singing and the ratings went up! Johnny was about to get the bigger surprise, when someone phoned in during his call-in segment of "One on One" and instead of praising Chelsea and Johnny's pairing, this caller threatened Johnny to get rid of Chelsea! Then the caller played back a certain section of the song, "Friendship" with the lyrics of "When other friendships are forgot, ours will still be hot," and then told Johnny that he belonged with them, not Chelsea! The caller then hung up. Johnny now knew he had an obsessed fan or, so he and much of Springfield thought! As the days went by, the obsessed fan continued to stalk both Johnny and Chelsea with more threatening phone calls. Johnny asked Frank Cooper to investigate, but the fan continued to stay one step ahead of him and the obsessed fan got more daring and personal. On December 18, 1989, unbeknownst to Chelsea and Johnny, while Chelsea visited Johnny's apartment to put up his Christmas tree and lights, the obsessed fan stood outside watching them through the window. Finally, Johnny became suspicious that the obsessed fan was really a stalker wishing to do Chelsea ill. Johnny would be proven right. On New Year's Eve, Johnny and Chelsea came to Johnny's apartment and found that Chelsea’s items were ransacked.
Four days later, on January 3, 1990, with Chelsea and Johnny singing "Friendship", Chelsea almost was killed when a piece of lighting equipment nearly falling on top of her. Almost everyone else at the station (Holly and Ross amongst them) assumed it was an accident; but near the end of the show, the "obsessed fan" called with a warning to Chelsea that this wasn't the worse that was about to befall her. Johnny now knew that Chelsea was being stalked. Things heated up soon after when the "fan" tried to run into Chelsea with a car and then later left another phone call at the station. Finally, two things occurred that seemed to point at WSPR employee Dana Jones being the stalker: Chelsea's stolen engagement ring was discovered in Dana's possession and Dana had been seen imitating Chelsea. At the end of the month, the stalker attacked Chelsea with a sharp letter opener! Luckily, Johnny was able to stop the stalker, even injuring the stalker's hand slightly. Chelsea then asked Rae if she could borrow her gun, and then agreed to move in with Johnny. Johnny was furious during the first few days of February when he found the weapon and promptly returned it to Rae. Johnny and Chelsea although concerned, proceeded with their plans for a Valentine's Day wedding. Rae was to be Chelsea's matron of honor and Rick was to be Johnny's best man. The wedding was to take place at Ed and Maureen's house and would be a rather small intimate gathering of a very few people, mainly the wedding party and Ed, Maureen and Michelle. However, things before the wedding even began Chelsea doubled over in pain! Rick, Ed and Johnny quickly took her to Cedars, where, sure enough, Rick found out that Chelsea had been poisoned.
Later, the stalker called during "One on One" and insisted that Johnny's show be replaced permanently by Nadine's "The Love Bug." Johnny refused to be intimated though and addressed the fan directly challenging them to show themselves at the station, of course the stalker refused. Later Rae Rooney told Chelsea at Cedars, that she suspected that Dana Jones was the stalker. In order to protect Chelsea, Johnny suggested that they appear to break up. Chelsea was released from Cedars and with not being with Johnny anymore went and lived with Rae. Later, Chelsea told Frank that she was convinced that Dana was the stalker and was still after Johnny; but Frank told Chelsea that he was equally convinced that Rae was the stalker; which Chelsea vehemently disagreed with. Very soon after their conversation, Frank would have a jolt that perhaps Chelsea was right about Dana. Frank found Dana going through Johnny's stuff! Dana tried to tell Frank and Johnny, who showed up shortly after this, her suspicion that the stalker was Johnny’s old girlfriend, Roxie, who had had a nervous breakdown. Of course Frank and Johnny were now even more suspicious of Dana. Tired of being a suspect, Dana decided to leave town and asked Chelsea to meet her at WSPR so they could talk. Chelsea complied only to have a pair of hands come up from behind her and start to strangle her. Chelsea struggled with her attacker and was able to give the attacker a quick kneed with her hand to the abdomen and the stalker let go and ran. Sure enough, Dana's fingerprints were all over Chelsea's scarf and Dana was arrested as the stalker. Johnny, believing the danger was now over, proposed to Chelsea again and Chelsea accepted. A couple of days later, an unknown person posted Dana's bail.
Upon her release, Holly convinced Dana to work the control booth for a newscast with Johnny one last time. Reluctantly, Dana complied and was shocked to see someone else in the booth ready to drop a light on Chelsea! A struggle ensued with Dana getting shot and the real culprit getting away. That day, Dana died at Cedars before she had a chance to name her killer. The stalker would turn out to be Rae herself. The reason she was stalking Chelsea was that she blamed her old roommate for her brother's mental condition because Chelsea never returned his affections. Her brother went crazy and landed in an institution. After he committed suicide, Rae continued to terrorize Chelsea. Finally Rae kidnapped Chelsea and threatened to kill her when Johnny and Frank found them and stopped her. After Rae went to jail, Chelsea and Johnny went on with their wedding plans. However, by then, Johnny received word that Roxie was making an improvement and with Chelsea's support traveled to Switzerland to see her. After a few weeks, Johnny returned and wanted to give Chelsea a good-bye letter but Chelsea found the letter before he had a chance. Enraged, she let him go and Johnny moved to Switzerland to be with Roxie.
Afterwards, Chelsea began to work as a nightclub singer in the Blue Orchid and started dating Fletcher Reade. However, when it became clear that Fletcher was still in love with Alexandra Spaulding, Chelsea broke up with him. Soon after, Chelsea received a phone call from Jackson Freemont from London in January 1991 who asked her to move to London so that he could support her singing career. Seeing no reason to stay, Chelsea accepted and left Springfield.
In 1993, the entire Reardon family returned to Springfield to attend Maureen's funeral. After the funeral, instead of going to Ed Bauer's, they gathered at their old home, the Reardon Boarding house.