Hit and run; hit Stuart with her car and fled the scene
Crashed into the a telephone pole that fell into the community center
Lied about who Stuart was, and paid him to stay away from Pine Valley
Plotted with Frank, a builder, to delay building of the Colmar Tower
Locked Stuart and Marian in the attic at Chandler Mansion
Staged a fall down the steps to cover up her miscarriage
Disguised herself as a waitress to get aboard a yacht hosting a party
Stole Vanessa Cortlandt's $500,000 pearl necklace
Adultery; Slept with a drugged Mateo
Sneaked into Lorenzo's hospital room and stole a lock of his hair
After Harry Vaughan died, Hayley escaped her alcoholic mother, showing up on Trevor's doorstep in Pine Valley. Arlene came to Pine Valley to bring Hayley back to Chicago and had a surprise encounter with Adam Chandler, her long-ago lover who was Hayley's biological father. Hayley was stunned by the news; she had always believed Harry Vaughan, who she loved very much, to be her father.
A drunken Arlene, traveling with Hayley, careened into a car driven by Jackson Montgomery, in which pregnant Brooke was badly injured. Hayley knew her mother's license had already been revoked for driving while intoxicated, so she pretended she was driving.
Arlene loved her daughter, but she couldn't resist her attraction to Alec McIntyre, who was engaged to Hayley. Arlene discovered that Alec was after Hayley's company, Enchantment, and she threatened to tell Hayley. Alec took advantage of Arlene's neediness and seduced her, getting a vow of silence out of her in the process. What Alec thought would be a one-night stand with Arlene quickly turned into more as Arlene continued to blackmail Alec in exchange for sex.
During this time Hayley befriended young Mateo Santos. Alec was jealous of Hayley's friendship with Mateo, and he pushed his plan into high gear. Alec and Hayley eloped, and Alec had Hayley sign papers for a joint banking account. Alec promptly emptied the account's funds, but Arlene was wise to him. Arlene once again blackmailed Alec for sex, but this time she secretly videotaped their encounter and got Alec to incriminate himself on tape.
Adam became suspicious that something was going on between Alec and Arlene. Adam wanted to protect Hayley and devised a plan to make Arlene think that Alec was having an affair with Gloria. A jealous Arlene then confronted Alec about cheating on her and a disgusted Alec thoroughly rejected her. When Arlene told Alec that she was going to tell Hayley everything, Alec had no choice but to meet with her one more time. By this time, Hayley was wising up to Alec's misdeeds. Alec arranged to meet with Arlene at an out of the way motel, unaware that Hayley and Mateo were following him. Once at the motel, Alec forcibly started pouring a bottle of alcohol down Arlene's throat. Alec knew that this would kill Arlene, who was an alcoholic, and that was just what he wanted. Hayley and Mateo walked in to witness the horrible scene and Alec's plan was foiled. Alec was arrested for his crimes and sent to jail.
When Arlene returned to town in February 2000, there were few people that were happy to see her. Drunk and behind the wheel, Arlen plowed into Stuart Chandler. Arlene stepped out of her car to see what had happened, but all she found was a shoe on the side of the road. Arlene panicked and drove off. Later that same night, Arlene smashed into a telephone pole and badly damaged the community center. Brooke took it upon herself to try to get Arlene help for her drinking problem, but her mission proved futile.
Arlene's time in Pine Valley wasn't all bad. Arlene insinuated herself into a police investigation that linked Trevor Dillon to the death of Sophie Malinowski. Janet had killed the woman, but Trevor took the blame so that Janet wouldn't go back to jail. Arlene pretended to be interested in an eye witness at the scene, named Billy Blue Taylor. Arlene got Billy to admit that he hadn't seen Trevor commit the crime and was just trying to stick it to Trevor for having busted him several years earlier. The case against Trevor was dropped and Janet and Amanda were free to rejoin Trevor.
Arlene later learned that Stuart wasn't dead. In fact, he had found his way to Nevada where he and Ester Glynn were living as husband and wife. Arlene paid a restaurant owner's daughter to keep en eye on Stuart so that no one would ever know that Stuart wasn't dead.
Hayley and Mateo were in the process of planning a wedding and Arlene wanted to be a part of it. She was banned from the wedding ceremony, but she managed a surprise showing at the wedding reception. A drunken Arlene and Adam accidentally wandered into the reception --- and Arlene gushed the news that she and Adam were husband and wife. The plan, as everyone would learn soon enough, was that Arlene's presence would keep Liza, Hayley and all of Adam's other family members at arm's length. Adam was grieving over what he believed was his part in his brother's death. In return, Arlene would get a sizeable chunk of money. Arlene and Adam drank it up on many, many occasions and despite their supposed "marriage of convenience" had sex at least a couple of times. Stuart returned to Pine Valley and Arlene locked him in the Chandler Mansion attic. When Adam was injured in a building collapse, Arlene figured that the only way to will Adam back to life was by releasing Stuart. Arlene did, but as she had feared she was soon an outcast for nearly killing Stuart and then for not telling anyone that he was alive. A few days later, Arlene learned that she was pregnant.
Arlene was ecstatic that she was pregnant and thought that the baby might help her hold on to Adam. She was wrong. Hayley and Mateo convinced Adam to give up parental rights to Arlene's baby and allow them to adopt the child. Arlene, though, was opposed to the idea. Arlene suffered a miscarriage, but she and Vanessa plotted to come up with a way to make the loss of the baby work in Arlene's favor. Arlene staged a fall down the steps at Chandler Mansion during an argument with Liza. That way, it looked as if Liza was responsible for the death of the baby.
Arlene was back in town briefly in September 2001 after Hayley had her baby Lorenzo, but she wasn't there just to see Lorenzo like she claimed, she wanted a child and had her mind set on Lorenzo. Adam and Mateo didn't trust Arlene for a minute and sent her packing on a plane to the other side of the U.S. Before leaving, however, Arlene managed to clip a lock of 'enzo's hair.