Fyre, as Kay Lee Ray, made her WWE debut at the October 8, 2015 tapings of NXT, losing to Nia Jax. In 2017, Ray was selected as one of thirty-two competitors in the first Mae Young Classic, where she lost to Princesa Sugehit in the first round on July 13. The next night, she competed in a six-woman tag team match alongside Jazzy Gabert and Tessa Blanchard where they defeated Marti Belle, Santana Garrett, and Sarah Logan.
At NXT UK TakeOver: Blackpool on January 12, 2019, Ray and Gabert appeared at ringside. It was later confirmed that the two had signed with WWE. On March 13, Ray made her NXT UK in-ring debut, defeating Candy Floss. At NXT UK TakeOver: Cardiff on August 31, Ray defeated Toni Storm to win the NXT UK Women's Championship; becoming the first British-born wrestler to hold the title.
On the 13 November 2019 episode of NXT, Ray interfered during a "WarGames Advantage" ladder match between Shayna Baszler's team member Io Shirai and Rhea Ripley's team member Mia Yim, helping Shirai win the match and revealing herself as the fourth member of Shayna Baszler's team in the first ever Women's WarGames Match. Ripley's team would go on and defeat Baszler's team at NXT TakeOver: WarGames.
At a 16 November 2019 taping of NXT UK, it was announced that Ray would defend the NXT UK Women's Championship against Toni Storm and Piper Niven in a triple threat match at NXT UK TakeOver: Blackpool II. On the 20 January 2020 taping of NXT, Ray teamed with Bianca Belair and Io Shirai in a six-woman tag team match against Storm, Rhea Ripley and Candice LeRae in a losing effort. Ray would go on to retain her title against Storm and Niven at Blackpool II. On the January 20 episode of NXT, Ray teamed with Bianca Belair and Io Shirai in a six-woman tag team match against Storm, Rhea Ripley and Candice LeRae in a losing effort. After NXT UK Takeover: Blackpool II, Ray and Storm's feud would continue. On the February 27 episode of NXT UK, Ray retained her title against Storm in a stipulation that if Storm lost, she could no longer challenge Ray as long as she was champion. After the match, Ray started a feud with Niven afer Niven watched Ray brutally attack Storm during the "I Quit" match. On April 2, Ray and Jinny successfully defeated Niven and Dani Luna.
On the September 24 episode of NXT UK, Ray retained her title against Piper Niven. On the November 5 episode of NXT UK, Ray and Niven's feud continued after Ray insulted Niven after Niven lost to Ray. Niven came out and attacked Ray in the ring and backstage. On November 19, Ray was again successful in defending her title against Niven in a Falls Count Anywhere Match when Jinny interfered as a result of Niven disrespecting her two weeks prior. In the following weeks, Ray retained her title in a championship match against Jinny and another title match against Meiko Satomura. On the June 10, 2021 episode of NXT UK, Ray lost the title to Meiko Satomura, ending her record-setting reign at 649 days.
On August 22, 2021 at NXT TakeOver: 36, Ray returned to the NXT brand at the conclusion of the NXT Women's Championship match. On the November 23 episode of NXT, Ray distracted Mandy Rose during her match against Cora Jade, causing Rose to lose the match. Later that night, she joined Io Shirai's team at NXT WarGames, seemingly turning face for the first time in her career. At WarGames, her team was victorious; during the match she teased turning on her team when she approached an injured Cora Jade with a kendo stick, only to turn and attack Kai instead. On the December 7 episode of NXT, Kay Lee Ray appeared in a backstage segment alongside Cora Jade and Raquel González, praising Jade's performance at WarGames and gifting Jade her baseball bat, cementing her face turn. On the February 8 episode of NXT, Ray fought Mandy Rose for the NXT Women's Championship, but lost. Ray and Io Shirai would later win the 2022 women's Dusty Rhodes Tag Team Classic and at NXT Stand and Deliver, Ray would fail to win the NXT Women's Championship in a fatal-four way involving Shirai and Cora Jade.
On the April 26 episode of NXT, Ray revealed her new ring name Alba Fyre. She would make her in-ring redebut on the May 10 episode of NXT, in a winning effort against Amari Miller. After defeating Tatum Paxley on the June 7 episode of NXT, Fyre was attacked by Lash Legend, starting a feud between the two. Fyre would defeat Legend on the June 21 episode of NXT by disqualification (after Legend used Fyre's own bat) and on the August 2 episode. At Halloween Havoc, Fyre unsuccessfully challenged Mandy Rose for the NXT Women's Championship. On the November 15 episode of NXT, Fyre lost her championship rematch against Rose in a Last Woman Standing match, when a returning Isla Dawn interfered. This led to a match between Fyre and Dawn at NXT Deadline on December 10, where Dawn was victorious. Fyre defeated Dawn in an Extreme Resolution match on the January 3, 2023 episode of NXT. Fyre would turn heel again and join forces with Dawn on January 31 episode of NXT. At Stand & Deliver on April 1, Fyre and Dawn defeated Fallon Henley and Kiana James to win the NXT Women's Tag Team Championship.
As part of the 2023 WWE Draft, Fyre, along with teammate Dawn, was drafted to the SmackDown brand while still the reigning NXT Women's Tag Team Champions. Fyre and Dawn made their SmackDown debuts on May 19, defeating Valentina Feroz and Yulisa Leon. On the June 9 episode of SmackDown, Fyre and Dawn was confronted by the WWE Women's Tag Team Champions Ronda Rousey and Shayna Baszler, who challenged them to a unification match, which they accepted. On the June 23 SmackDown, Fyre and Dawn lost the NXT Women's Tag Team Championships to Rousey and Baszler. Fyre and Dawn returned on the December 22 episode of SmackDown, attacking Damage Control during a "Holiday Havoc" match. Soon after, the team of Fyre and Dawn began competing under the team name of The Unholy Union.
During night one of the WWE Draft on April 26, Fyre and Dawn were drafted to the Raw brand. On June 15, at Clash at the Castle, The Unholy Union defeated Bianca Belair and Jade Cargill for the WWE Women's Tag Team Championships in a triple threat tag team match also involving Shayna Baszler and Zoey Stark, making The Unholy Union the second female tag team to have won the WWE and NXT Women's Tag Team Championships. On July 30, Fyre and Dawn successfully defended the titles against Lash Legend and Jakara Jackson of The Meta-Four during week one of The Great American Bash.