Burchill made her WWE television debut on the February 11, 2008 Raw (airing on tape delay from the previous week) as the on-screen sister of Paul Burchill. The two originally displayed early signs of a gimmick based around incest, with Paul using the catchphrase "whatever Katie wants, Katie gets", but the incest indications soon stopped. At WrestleMania XXIV, Lea was one of the lumberjills in the Playboy BunnyMania Match, in which Beth Phoenix and Melina defeated Maria and Ashley.
After appearing alongside Burchill on WWE Heat, Lea made her in-ring television debut on 28 April episode of Raw defeating Super Crazy in an intergender handicap match along with Burchill.
On 19 May, on Raw, she had a confrontation with the Women's Champion, Mickie James, where she insinuated James had used her relationship with John Cena to sleep her way to success. Two weeks later, Lea teamed up with Beth Phoenix in a winning effort defeating James and Melina, in which she pinned James. On the 16 June episode of Raw, Lea and Burchill defeated James and Mr. Kennedy in a mixed tag team match, where Lea pinned James a second time, thus earning a title shot. At the Night of Champions pay-per-view, Lea challenged Mickie James for the WWE Women's Championship, but was unsuccessful in capturing the title. On the 14 July episode of Raw, Lea once again challenged James for the Women's Championship, but was unsuccessful. After she and her brother beat James and Kofi Kingston, she received another chance at James' title in August but failed to win.
She closed out the year by appearing tag team matches, regularly teaming with Jillian Hall. On the last Raw of the year, she made an appearance in a battle royal to determine the next challenger for the Women's Championship, which was ultimately won by Melina.
Two days later, on 30 December, it was revealed that Lea and Burchill had been moved to the ECW brand, but failed to make an impression with Burchill losing to continue DJ Gabriel's winning streak. Going into 2009, Lea made a better impact in her ECW on Sci Fi debut with a win against Gabriel's partner Alicia Fox. However, the Burchills lost a tag team match against Gabriel and Fox the following week.
On 5 April 2009, she competed in the 25-Diva battle royal at WrestleMania XXV, but the match was won by Santina Marella. Lea wrestled again in July 2009 against the newly-drafted Bella Twins. First facing Nikki, Katie took the advantage but Nikki swapped places with her twin sister, fooling both Katie and the referee, causing Katie to lose. Two weeks later on WWE Superstars, the twins made the same switch in reverse order after the referee could not differentiate between the two and Lea lost again.
From August towards the end of 2009, Paul became embroiled in a rivalry with backstage interviewer Gregory Helms, over whether he was also in-ring performer The Hurricane. They agreed to settle the matter in a match on 17 November episode of ECW, which saw Hurricane's mask put up against Burchill's career on the ECW brand. Despite many attempts, Paul could not secure the pin and subsequently lost the match, resulting in both he and Katie Lea leaving ECW. The following week on ECW, Katie Lea and Paul, now sporting masks and calling themselves The Beautiful Nightmare and The Ripper, respectively, appeared in a backstage segment with General Manager Tiffany and asked for a contract, which Tiffany said they would receive if The Ripper could defeat The Hurricane the next week on ECW. However, The Ripper was unmasked by Hurricane and subsequently defeated in their match, resulting in Katie and Burchill remaining off ECW.
On 11 January, 2010, Lea moved back to the Raw brand without her brother Paul Burchill, by competing in a first round tournament match for the vacant Divas Championship, but lost to Eve Torres. At the Royal Rumble pay-per-view, Katie Lea teamed up with Maryse, Natalya, Hall, and Alicia Fox in a losing effort to the team of Gail Kim, Kelly Kelly, Eve Torres, and The Bella Twins. On 26 February, Paul was formally released by WWE, leaving Katie to appear on her own, but she was released from her WWE contract two months later, on 22 April.