Britney Spears made a notable guest appearance on the TV show How I Met Your Mother during its third season. She played the character Abby, who is the receptionist at Stella Zinman's dermatology clinic. Abby quickly develops a crush on Ted Mosby, who is visiting Stella to have a tattoo removed. Despite Abby's obvious interest, Ted is focused on Stella, leading to comedic situations. Spears appeared in a two-episode arc, first in season 3, episode 13 ("Ten Sessions"), and later in episode 19 ("Everything Must Go"). In the latter, Abby and Barney Stinson pretend to be in a serious relationship to make Ted jealous

. Britney Spears herself was a fan of the show and approached the creators Carter Bays and Craig Thomas to be part of it. Initially, the creators considered casting her as Stella, a more central character, but decided to create the role of Abby for her instead, as they felt Spears was better suited for the comedic and lighter role. Alicia Silverstone was originally slated to play Stella but dropped out due to concerns about being overshadowed by Spears

. Spears' cameo was significant for the show’s popularity. Her appearance brought a major boost in ratings and helped increase the show's visibility during a critical period. The creators credited her with helping keep the series alive, as her comedic timing and performance impressed the cast and crew. This cameo marked Spears' return to entertainment after a hiatus and was well-received both by fans and the show's team

. In summary, Britney Spears played Abby, Stella's receptionist, in How I Met Your Mother season 3, contributing to a memorable and impactful guest role that helped the show gain popularity and survive a challenging time.