Helena is the illegitimate daughter of Fame Douglas and his former mistress Maria, a world class soprano opera singer. Seemingly distant from her father and his work, when he was murdered Helena was devastated, but hardly affected. On the other hand, she loved her mother dearly and followed in her footsteps, becoming a famous opera singer in her own right.

While performing at the Great Opera House, she was targeted by Christie using a sniper rifle. Maria, who was present with her, spotted the rifle at the last second and dove in front of her daughter. Maria was killed instantly. The assassin fled, leaving Helena alone in great shock and covered in her mother's blood. Helena set out for vengeance for Maria's death.

While searching for the assassin, she discovered that the murders of her parents, and attempt on her own life are somehow related to the Dead or Alive World Combat Championship. Helena entered the tournament to discover the truth.

Although never explained in the series, Helena somehow learned of information pertaining to DOATEC, most notably the ill-fated Project Epsilon when she encountered Hayate suffering from amnesia. She confused the amnesiac Hayate (or "Ein" as he was known as at the time) by talking to him about the Epsilon Project, but he didn't remember anything about it. In the end they fight and Helena was defeated by him. She then goes on to face Gen Fu. Gen Fu wondered why Helena joined the tournament, but Helena wouldn't answer and decided to fight him instead. Helena was the victor of the fight.

During the tournament, she also encountered Ayane. In this encounter, she accused Ayane of being her mother's murderer. Ayane neither confirmed nor denied having killed Maria and teased her, after which a fight broke out between the two. Helena lost to Ayane and was knocked out of the tournament. Helena was not brought down by the defeat and still wanted to avenge her mother's death.

For some time, Helena tried to find out the truth about Project Alpha and its real purpose, but Victor Donovan ordered Lisa Hamilton and Christie to keep her from finding out.

After the second tournament, Helena was captured by Donovan and imprisoned. Although Helena, the reluctant heiress of DOATEC, stated that she didn't have any connection with the organization, Donovan told her that the only way to obtain her freedom and know the truth behind DOATEC is to win the third tournament. In the meantime, Donovan assigned Christie to keep an eye on Helena by acting as a servant to her and, should the need arise, kill her if she discovers too much.

During her time in the tournament, Helena hired the assassin Bayman to be her bodyguard as well as to kill Donovan.

During the rounds of the tournament, Helena encountered Hayate once again, who had fully regained his memories. Hayate demanded her to tell him why Genra joined DOATEC, but she claimed she didn't know, that Genra and even herself were just puppets that DOATEC could control. After defeating Helena in battle, he told her that he would defeat Genra, and she should leave DOATEC for her own safety.

As the tournament went on, Helena soon confronted Christie, where the latter admitted that she was an assassin sent to kill her. Bayman managed to capture Christie, but when Kasumi α heard that Helena wanted her creator dead, she attacked, though Helena managed to defeat her.

Helena did not win the tournament, as the title of the winner went to Ayane.

She was later given an invitation for a supposed Dead or Alive tournament that was going to be held at Zack Island. However, she discovered alongside the rest of the prior participants that it was a hoax, but decided to make the best of their situation for the two weeks on the island.

Helena, as the daughter of former chairman Fame Douglas, took control of DOATEC and joined the fourth tournament with the other fighters.

It is here that Helena met Kokoro, in which she learned that Kokoro is her biological half-sister and that perhaps their blood brought them together. Afterwards, the Tritower comes under attack by the Mugen Tenshin clan. During the attack, Helena came across Lisa, who admitted that she tricked Hayate into stopping Donovan.

She was then confronted by Kasumi who told her to stop the fight between DOATEC and the Mugen Tenshin. Helena refused and tells her that her clone, Alpha-152, would soon be awaking causing havoc in the world. She attempted to kill Kasumi, only to be stopped by Ryu Hayabusa and was defeated by Kasumi. After her defeat, Helena was then confronted by Christie, who revealed that she was the one who had killed her mother whilst attempting to assassinate Helena. Boiling with anger, Helena fought Christie. The result of the fight is unknown (although it's highly likely that Helena was the victor). While Christie escaped, Helena decided to go down together with DOATEC and subsequently activated the Tritower's self-destruct.

Plagued by flashbacks of her deceased mother, she moved up to the helipad between the three towers that make up the complex, willingly giving up her life and letting herself be consumed by the flames of the burning buildings, as Kasumi and Ayane helplessly look on. Suddenly, Zack came flying in with a chopper and saved her before the building fell to dust. Although Helena did win the fourth tournament, she gave up the title to Zack.

Some time afterward, Zack invited Helena to New Zack Island, a resurrected version of the one that sunk due to a volcano erupting, under the pretense of discussing with him how to revive DOATEC. She apparently took him at his word about spreading peace to the galaxy by creating a space station HQ for DOATEC, with Lisa teasing her about it, as well as teasing her about implications of a marriage proposal from Zack.

Over the next two years, Helena rebuilds DOATEC, making it stronger than ever, and announces the fifth tournament. She sends Zack, who is now under her employ, to travel around the world to gather the strongest fighters ever to compete in the new tournament.

On the Freedom Survivor, Helena is confronted by Bayman, who has survived an attack on him and his group of mercenaries in the Middle East and demands from her an explanation. Helena denies any involvement of DOATEC and herself regarding the attack, and Bayman furiously leaves to find his answers. Kasumi, who is later revealed to be a clone of the original, then appears out of hiding and asks Helena where Alpha-152 is. Helena assures the ninja that her clone will be found. When Helena has Hayate brought to the yacht by Zack, they both tell Kasumi that she should not handle the clone on her own, but she does not listen to them and hastily leaves the ship.

At the Taylor's Bar, Helena reunites with Bass and has a friendly conversation about his retirement from wrestling while he plays pool. But when Christie suddenly appears and budges in on Bass's game, Helena asks her what she's doing there. The assassin coldly replies that she's looking for a real man and the two of them fight. Then she meets up with Kokoro, who was just brought to the bar by Zack, and the two of them have a friendly conversation about Miyako and her work, and their father Fame Douglas. Wanting to see how stronger she has gotten, Helena asks Kokoro to fight her.

The next day, Helena spots Lisa and Miyako arriving at the oil rig and becomes very suspicious about them because they did not let her know that they were coming. When she demands an answer, Lisa fights her but is presumably defeated. Some time later, Helena meets with Hayate, Ayane and Hayabusa on the Freedom Survivor and tells them that Donovan's new organization, MIST, may have existed within DOATEC without them knowing and that he is already on Phase 4 of his Alpha plan: the creation of soldiers with the fighting capabilities of the ninja and the distribution of them to countries with powerful militaries. Knowing that she cannot confront Donovan and MIST directly due to her reputation, she allows the ninja to infiltrate the rig and stop Donovan's plans. Helena also tell the three ninja that she has sent Kasumi to the oil rig, where Donovan's laboratory is hidden, to find Alpha-152.

After the destruction of the oil rig and the MIST laboratory, Helena watches on her yacht as the real Kasumi gives her thanks to her ninja brethren and takes her leave. Both women make their own vows to defeat Donovan once and for all.

Shortly after the fifth tournament, Helena accepts an invitation from Zack to go to New Zack Island. She at first wonders what he is planning this time around, though decides that it is none of her concern and wants to take a break. She also proposes her maid Marie Rose should take a vacation, too.

On the last day on the island, she felt so well about the break that she forgot almost everything about work. She was also proud of the work done by the substitute that Zack had hired.

After the new DOA Colosseum has been built, Helena tasks her servant Marie Rose with keeping an eye on a new fighter named Honoka, predicting that MIST will come after her for "something much worse." When Hayate comes to her office, he demands Helena explain the explosion on DIG and remarks about Rig being there, causing Helena to become suspicious about the former oil platform worker’s other life.

Some time later, Kokoro arrived with a photograph depicting the two of them as children alongside Fame Douglas, explaining that a woman named NiCO gave it to her. Helena reluctantly reveals that they are sisters and this causes Kokoro to snap and try to find her mother but Helena tries to stop her. Overpowered by her younger sister due to not fighting at full strength, Helena begs Kokoro not to leave after Kokoro sadly says goodbye as she is the only family she has left and she must protect her, ultimately succeeding in convincing her.

By the time of Raidou’s resurrection within one of MIST’s secret headquarters, Helena enters the base to meet NiCO. Upon realizing what NiCO’s plan is, Helena disapproves of bringing their lost parents back to life, citing that one needs to move on and vowing that NiCO will someday learn to move on from her pain as Helena has.

At some point, Helena heard about the Venus Festival, as well as rumors that it was a front for a conspiracy. She went to the island to investigate, under the guise of taking a vacation, while admitting that she'd like to be surprised overall. She also brought Marie Rose along, who ultimately ended up choosing to participate in the festival independently in order to prove to Helena that she was an adult.