Underwood will make her acting debut on the CBS sitcom as a love interest for Ted (Josh Radnor), CBS confirmed. Her character, Tiffany, is an enigmatic pharmaceutical sales rep.

The episode is scheduled to air in March.

“How I Met Your Mother” airs its 100th episode on Monday. The episode, titled “Girls vs. Suits,” finds Barney (Neil Patrick Harris) trying to score a night with the hot, new bartender at MacLaren’s, played by guest star Stacy Keibler. Barney’s plan hits a snag when Keibler’s character announces that she hates guys in suits. The dilemma leads to “Nothing Suits Me Like A Suit,” a big song and dance number featuring the entire cast, a host of backup dancers and choreography by “Glee’s” Zach Woodlee.