Lisa Hamilton (also known as La Mariposa) is a luchadora and a former scientist of the DOTEC of Dead or Alive series. Lisa has a mysterious, shadowed past that has not fully come to light yet, and has links with many others despite being relatively new to the series.
Not much is known about Lisa's life before DOATEC, although it is well-known that she was high school friends with fellow wrestler Tina Armstrong and was a member of her school's volleyball team, which explains her great volleyball skills. At some point during her life, Lisa became one of the head scientists for DOATEC at DOATEC Germany, working for Victor Donovan during his genetic projects and becoming an luchadora at the wrestling contest along with Tina.
Project Epsilon and the Second Tournament
Lisa was known to be in charge of two DOATEC projects -Project Epsilon and the more successful Project Alpha - and was in charge of watching over the projects' test subjects,Hayate and his younger sister Kasumi, as well as Kasumi α, who was a prototype product of Project Alpha.
When Helena Douglas was hosting a public gathering on theFreedom Survivor to announce her take-over of DOATEC and the start of the second Dead or Alive World Combat Championship, Lisa attended the speech and found Ryu Hayabusa in the crowd. She asked him if he would be joining the tournament, but Hayabusa wasn't interested in talking her so Lisa ended up insulting him for coming second in the first tournament. However, she apologized and they ended up going back to her cabin. While Lisa was bathing, Hayabusa overheard her talking about Kasumi to Donovan over the phone and he soon left to save her.
Around the time Lisa returned to DOATEC Germany, Hayabusa attacked the building and set it on fire. After Lisa ordered the evacuation procedures, she found that, during the chaos, Alpha had released Kasumi from her cell and she found out that her older brother was in the facility. Lisa became very annoyed with Alpha for telling Kasumi but, as Kasumi demanded to see her, the woman calmed quickly and drew out a handgun to keep Kasumi quiet. At that moment, Hayabusa broke into the building to take Kasumi to safety, letting Lisa and Alpha escape by helicopters, along with Hayate.
During the escape, the helicopter Lisa and Hayate were in experienced engine problems and crash-landed in the Black Forest. They both lived but Hayate somehow got separated from Lisa and was saved by Hitomi.
At some point, she was hired to act as public relations for Zack Island. She then spent the next two weeks on vacation at the island.
The Fourth Tournament and the Fall of DOATEC
Despite what happened at DOATEC Germany, Lisa continued to work on Project Alpha and at times even had to protect the project from being discovered by Helena, which included threatening the woman's life.
At some point just before the fourth tournament, Lisa seemed to have a change of heart about the project and its wicked goals and planned to help to take down DOATEC as her persona "La Mariposa." During the early stages of the tournament, she engaged Tina Armstrong in a no-holds-barred wrestling match.
While the Mugen Tenshin clan attacked DOATEC's main headquarters, Lisa also confronted Hayate and told him that she was the one who manipulated him. He "thanks" her with a fight. She also revealed this to Helena Douglasduring the tournament.
After the tournament, she went on to fight in a team wrestling match alongside Tina. It's possible, since DOATEC is no more, that this means that Lisa decided to follow a professional career as a luchadora.
New Zack Island
After the tournament, she proceeded to conduct a similar role before at New Zack Island, acting as the public relations official at the island, as well as spending vacation there. She also teased Helena Douglas (who had come to the island to discuss a business proposal relating to DOATEC's revival) regarding his claim that he intended to use DOATEC to bring peace to the galaxy, much to her chagrin.
The Fifth Tournament and MIST
After the fourth tournament, Lisa is working for Donovan with his new organization: MIST. He sends her to Tokyo to meet his client, but she is confronted by Hayabusa, who has overheard her conversation with Miyako on her cellphone and has confirmed MIST's existence. While Lisa tells him that it's her duty as a scientist to make new discoveries to change the world, Hayabusa replies that her discoveries have only brought suffering to him and his friends, and battles her afterwards. While escaping, Lisa accidentally bumps into Kokoro, who fights her with a demand for an apology. After the fight, Lisa asks Kokoro how Miyako is doing.
During the fifth tournament, Lisa makes contact with Miyako without Helena's knowledge, drawing suspicion. When they visit the oil rig, Helena demands to know why they are their without her knowledge. Lisa refuses to answer and steps up to fight Helena but she is defeated.
In the last chapter, there is some evidence that Lisa is a double agent working against Donovan like she did in the previous tournament. At the oil rig, Lisa finds Kasumi in the lab trying to free Hayate, who had been captured byRig. Lisa realizes that Donovan is reactivating Project Epsilon and frees Hayate. When the four ninja fight Alpha-152, Hayabusa and the clone launch a ninpo at each other. The impact of their attacks creates a huge explosion, destroying the lab in the process. Lisa is seemingly trapped under the debris and her cry is heard; but she ultimately survived, although with severe enough injuries that she had to undergo rehabilitation for a time.
The Sixth Tournament
As Lisa manage to survive from the explosion of MIST’s first secret lab at DiG, she also created a prototype immunity system to prevent Epsilon effects from freezes Hayate in limited time. Although she remained loyal to Helena, Lisa has her own rights on not wasting time before Victor Donovan get away with his crimes quickly.
Before the sixth tournament started, Lisa visits her old friend, Tina and being introduced by her to Mila at Gym the gym.
At the Hot Zone section of the Memorial Museum, Lisa begin to concern about what has happened to the Phase 4 who attacked Bayman at the said war zone location since then. Shortly, she is approached by her “replacement” at MIST named NiCO. After defeating NiCO, Lisa warned her about trusting Donovan, but NiCO refused and appears to be already aware who he is. When Honoka was kidnapped by MIST, Lisa is last seen preparing Hayate the prototype Epsilon immunity system before the wind ninja went to MIST.