While Emma Frost was laying in a comatose state, the Dr. John Sublime harvested eggs from her to begin experimentation. The Weapon Plus program began the cloning to develop a powerful weapon capable of killing every mutant on Earth by combining their telepathic abilities. The project was designated Weapon XIV and girls were incubated and artificially aged inside the subterranean level of The World. Thousands of girls were cloned from the ovum, but while the others remained dormant, five girls were sent to infiltrate the Xavier Institute as students sisters to hone their talents for Sublime's purposed.
After the Xavier Institute went public, the orphan quintuplet sisters Sophie, Phoebe, Mindee, Celeste, and Esme were enrolled. To protect their secret origins, the girls unconsciously place mental blocks in the minds of the faculty preventing them from investigating their background.
The girls quickly gained the moniker "The Stepford Cuckoos", though their chosen codename was the Five-In-One. Emma Frost assisted the girls when Esme had a crush on student that turned out to be Stuff, an advanced guard of the Shi'ar. This sparked Emma taking a special interest in the girls, and the Cuckoos becoming her protégés. As gifted telepaths, they were registered into Professor X's psychic course along with their rival Quentin Quire.
Quire developed a crush on Sophie, but the Cuckoos considered him to be odd and completely rejected him. Sparked by learning that he was adopted and his uncontrolled powers, and fueled by use of the drug Kick, Kid Omega led a rebellion of students at the X-Mansion. To stop Kid Omega and his Omega Gang, Sophie and the other Cuckoos covertly snuck into Cerebra. Using Kick to amp up her powers, Sophie and her sisters were able to stop Quire. Unfortunately, Sophie died in the process. Unbeknownst to the others, Sophie was actually being influenced into these actions by Esme, who was also using Kick.
With the death of Sophie, the Five-In-One became the Four-In-One. The girls were furious with Emma Frost, whom they blamed for Sophie's death. To exact their revenge, they informed Jean Grey of the psychic affair between Emma and Cyclops.
Not long after Sophie's death, Esme attempted to murder Emma by shooting her with a diamond bullet. While Bishop and Sage investigated the murder, Esme fled the X-Mansion fearing that the truth would be revealed about her involvement in the deaths of Sophie and Emma. Fortunately, Emma was saved by the combined efforts of Beast and Jean Grey with the Phoenix Force.
When Esme returned, it was alongside her lover, Xorn posing as Magneto and his Brotherhood of Mutants. Esme and Xorn had both become mentally unstable through excessive use of Kick. When Xorn's affection were withheld from her, Esme turned on him, and Xorn killed her by burying her metal earrings in her brain. With the departure of Esme, the Four-In-One now became the Three-In-One.
The girls were among the students temporarily relocated to an X-Corp building in Salem Center while the Institute was being rebuilt. It was here that Mindee's first boyfriend, Germaine, died during an anti-mutant riot.
When the Institute was rebuilt under the leadership of co-headmasters Cyclops and Emma Frost, the students were organized into several training squads with an assigned mentor staff member. The Three-In-One was assigned to the Corsairs Squad under the tutelage of Cyclops with girls serving equally as co-leaders of the squad.
When Wing was injured from his altercation with Ord, the Cuckoos summoned Elixir to heal him.
When the Phoenix Force returned to Earth in search of a new host, it briefly considered the girls along with Kid Omega and Emma Frost before resurrecting Jean Grey. The Phoenix Force awoke Kid Omega, still in love with Sophie, exhumed her in hopes of reuniting with her. However, upon her resurrection, she promptly rejected Quire and died again. While the X-Men rushed to intercept the Phoenix, the Cuckoos remained in Cerebra as communication central.
On M-Day the vast majority of the world's mutant population was depowered. The Cuckoos retained their powers, but they were three of only 27 students to retain their powers. Fearing for the students' safety, Emma Frost ordered that the depowered students and staff leave the Institute. For their safety, the depowered students were brought through the Morlock Tunnels to an awaiting bus. Unfortunately, the bus of depowered students was bombed by anti-mutant zealot Rev. William Stryker, killing 42 of the former students on board.
The remaining students were placed by Emma Frost into an all-out brawl, and the ones deemed the best by Emma would become a group of New X-Men in-training. This entire exercise was met with disgust by the Three-In-One, who promptly informed Cyclops of Emma's actions.
When an unstable fraction of the Phoenix Force sparked inside the girls, their Weapon Plus nanotech dormant inside their bones was activated. This nanotech briefly reanimated Sophie and Esme, who directed their sisters back to The World to activate Sublime's plan for the destruction of the mutant race.
The Phoenix and Sublime both wrestled for control of the Cuckoos when the X-Men arrived. Phoebe and Mindee were captured and integrated into Sublime's machine, but the Phoenix was able to possess Celeste. When Celeste was finally merged into the machine, the Phoenix was divided between all the Cuckoos and trapped in their newly emerged second mutation, organic diamond hearts. This event finally activated the Thousand-In-One.
Celeste continued to resist the Phoenix and Sublime's machine long enough for the X-Men to forcibly disconnect them. However, in a rage, Phoebe triggered a power surge causing an explosion. However, Celeste was able take full control of the Phoenix, destroyed her sisters, and trapped the Phoenix fragments inside the Three-In-One's flawless diamond hearts rendering them emotionless.
After returning to the Institute, the girls adopted a rebellious/mischievous streak. They helped Elixir telepathically gain a PhD level knowledge of science and biology from Beast's brain. Along with the other students, they were pulled into Limbo, where they were rescued by Prodigy. To repay his kindness, the Cuckoos restored all of the knowledge he had previously gained with the use of his powers despite his powers being deactivated. When the Hulk came to the Institute to attack Professor X, the Stepford Cuckoos used Cerebra to contact other X-teams such as Excalibur and X-Factor Investigations for assistance. The sisters were briefly considered as potential candidate recruits for the Initiative.
After the birth of the Mutant Messiah, the Stepford sisters were stationed in Cerebra to search for the baby and act as central communication for the various X-squads.
The Stepford Cuckoos rejoined the X-Men and the last of mutantkind in San Francisco. During the Skrull Invasion, they assisted in the evacuation of a San Francisco Hospital, and later offered remote support to Emma while was bringing down the Skrulls' psychic blockade.
The Cuckoos aided Elixir and the X-Force briefly when Elixir was wanting depart the team. Out of loyalty to Cyclops, they agreed to maintain X-Force's secret status.
Once they relocated to Utopia, the Stepford Cuckoos frequently manned Cerebra. When Lobe, Scalphunter with a group of Predator Xs attacked Utopia, the X-Men were forced to battle the mutant eating creatures. The Cuckoos served as telepathic communication for the team, but during the battle the Phoenix fragments that were contained inside their diamond hearts escaped, and mysteriously returned to space, leaving the girls unconscious. When the girls recovered from their coma, they recruited Rogue to borrow their telepathy to help search for the Phoenix, but with no luck. Later the girls fell into a depressive funk due to the loss of their Phoenix powers.
While on a brief trip to Manhattan, the girls beat Spider-Man to thwarting a bank robbery.
Although not on the active roster for any one team, the Stepford Cuckoos continued to offer remote telepathic and Cerebra-based support for Cyclops, the X-Men, X-Force, Hope and her Lights, Magneto, and the Extinction Team.
When the Chaos King put the living asleep and opened the underworld, both Sophie and Esme were among the resurrected. Although, tension ran high between the two, they were able to help defeat the Carrion Crow and resolve some of the issues surrounding their deaths.
After Cyclops and Wolverine decided to part ways, Phoebe wanted to return to Westchester while Mindee wanted to remain on Utopia. With the deciding vote left to Celeste, she opted to stay on Utopia, partly because of Quentin Quire's presence at the school.
When the Phoenix Force returned to Earth searching for a new host leading to the war between the Avengers and the X-Men, the Stepford Cuckoos were among the younger X-Men detained in the Avengers Compound with the Avengers Academy. Afterword they were reluctantly recruited to the new Jean Grey School where they manned Cerebra and witnessed the death of Professor X and the reemergence of mutantkind.
The girls were very displeased with the new school. When Cyclops and his X-Men came to the school looking for recruits to their mutant rebellion, the Stepford sisters and Angel volunteered to go.
The girls joined and assisted Cyclops' team as the resident telepaths since Emma's powers were broken. During this time, Irma dyed her hair black and expressed that she wished to attain more individuality. Phoebe entertained the thought of doing the same, and eventually dyed hers red, although Celeste was upset, and Emma was supportive of her choice as well.
Later, following an attack from the future Brotherhood of Mutants, the Stepford Cuckoos and Emma Frost combined their telepathic abilities in an effort to defeat Xorn (Jean Grey). Although they were initially able to hold their own, they were all defeated leaving Xorn to continue the psychic duel with her younger counterpart.
In the animated series Wolverine and the X-Men, The Stepford Cuckoos (voiced by Tara Strong) appear alongside the Inner Circle in the three part episode "Foresight". They assist Emma Frost into tricking Jean Grey to release the Phoenix Force. After the Inner Circle betrays Emma, the Cuckoos are ordered to finish the job. All five serve as hosts for the Phoenix Force and wear the traditional red and gold Dark Phoenix costumes.
As warned by Emma, the Phoenix Force becomes too powerful for the Cuckoos to control. It leaves their bodies after Jean Grey calls to Phoenix, asking it to return to her body. However, as the Phoenix Force attempts to return to Jean, Emma intercepts the Phoenix and sacrifices herself to destroy it.
Video Game History
The Stepford Cuckoos appear as antagonists in the video game X-Men Legends II: Rise of Apocalypse voiced by Jennifer Hale. They are encountered in the Madri Temple and end up handing Emma Frost over to Apocalypse. They fight the X-Men alongside Holocaust who serves as their protector. There was a reference that they left the X-Mansion when their fourth sister was killed in action in a recent mission.