Lena Kundera arrived in Pine Valley in January 2003 when she was hired as Enchantment's Chief Financial Officer. Lena appeared confident and trustworthy, until she began skulking around the halls and asking for access to areas and files that she should not otherwise be interested in. It was discovered that she was Michael Cambias' spy -- and lover -- and had been ordered to undermine Enchantment, one of Cambias' targets for a hostile takeover. After Michael's attempts to nab the "recipe" for an anti-aging cream failed, he ordered Lena to seduce Erica's daughter, Bianca. By this time, Lena had already developed genuine feelings for Bianca. She attempted to flee the country, but Bianca convinced Lena to stay in town and give their relationship a chance. Later, Michael threatened the safety of Lena's mother, whom she had hidden in a villa somewhere in Europe. Lena had also stolen money from Enchantment and made it appear that Erica had hired someone to file a bogus lawsuit against upstart Fusion Cosmetics. Kendall Hart told her estranged mother, Erica Kane, what Lena was up to and the two created a pact to bring down Michael Cambias. Kendall also tried to warn her half-sister, Bianca, that Lena was using her, but Bianca didn't believe her. Until, that is, Bianca overheard Michael and Lena talking.
Bianca set up Lena, allowing her to be alone in Erica's penthouse. As Bianca watched over the secret surveillance cameras, Lena helped herself to the combination to Erica's safe from Bianca's purse -- and then to a secret formula for an anti-aging cream from Erica's safe. Lena would stumble across the security cameras a few days later and confessed her crime to Bianca. At a press conference staged to expose Michael and Lena's crimes, Bianca took pleasure in exposing what Lena had done even though she'd "promised" she would turn Lena over to the authorities. District Attorney Jack Montgomery agreed to drop the charges against Lena if she agreed to testify against Michael. Another surprise at the press conference was the appearance of Lena's mother, Paulina. Lena's mother explained to Bianca the hardship that Lena had faced her entire life. Her father had been branded a traitor and killed when Lena was young. Lena had done anything she could to get her and her mother out of Poland, only to wind up in the quicksand known as Michael Cambias. Bianca was more forgiving of Lena's actions, but only when Lena was cleared of the insider trading did Bianca reconcile with her. They even planned a vacation to celebrate their newfound honesty and commitment to one another. Lena found inner peace, happiness, for the first time in her life.
Lena did not leave town, she only left Bianca's side to help Adam Chandler bring more evidence against Michael Cambias for insider trading. Lena returned that evening to Myrtle's Boarding house to see Bianca. Lena believing Bianca was asleep left Bianca a love note. Bianca had already left Myrtle's for the park in order to burn her clothes and hide the evidence of her rape. Lena was bereft, repeatedly begging Bianca for another chance. When Lena learned that Bianca had been raped by Michael, she was devastated. She (along with everyone else in town!) threatened to kill Michael, and was seen throwing a gun into the docks the night of his disappearance. Several days later, she tried to kill herself by taking rat poison. Thankfully, Boyd and Kendall found her just in the nick of time.
Weeks later, Lena was arrested for poisoning Michael's allergy pills. Bianca rallied to her side and they became close again. Lena was released when they deduced that Michael had died before he could have taken the pills. Lena was again suspected a few months later, but ultimately, to everyone's horror, Bianca realized that SHE had killed Michael and blocked the incident out of her mind.
With that matter behind them, Lena adjusted to the fact that Bianca was pregnant with Michael's child. They were happy for a few months, but were devastated when Bianca's child was a stillbirth in April 2004 (the child was alive, but neither woman knew that at the time). While they attempted to piece their lives together yet again, Lena's mother called from Chicago. She had liver cancer and wanted to return to Poland before she died. With Bianca's blessing Lena reluctantly accompanied her mother, but gave her true love a ring and pledged to be back someday.
The distance between Lena and Bianca soon proved to be a sticking point in their relationship. Lena issued Bianca an ultimatum: visit her in Poland or end their relationship. Bianca ultimately stayed in Pine Valley and she and Lena went their separate ways.