Initially introduced in season 4, Holly served as a replacement HR Representative for the Scranton branch of Dunder Mifflin, and quickly developed a romantic relationship with Michael Scott, the regional manager.

After facing numerous challenges in their relationship, Holly and Michael ultimately get engaged and move to Colorado towards the end of season 7.

Holly arrives at Dunder Mifflin to serve as the replacement for Toby Flenderson, the previous HR Representative for the Scranton branch.

Michael initially dislikes Holly because she is part of Human Resources, but quickly falls in love with her after she playfully makes a joke about Toby's dullness.

Holly is subjected to hazing by co-worker Dwight Schrute, who convinces her that Kevin Malone is mentally challenged, a belief she continues to harbor until season 5.

Michael, who does not pick up on several hints that Holly has given him about attending the concert with her, purchases the tickets from her and rips them to pieces.

This, in addition to feeling no connection with Jan's baby, prompts Michael to apologetically hug Holly and ask her out on a date, which she accepts, visibly moved.

While organizing a fundraiser, CFO David Wallace notices Michael and Holly kissing, and realizes they are in a relationship.

She and Michael plan to continue dating, but ultimately decide to break up, realizing on the trip that the distance is insurmountable.

In "Garage Sale", she discovers that her aging parents need assistance and decides to move home to Colorado.

She accepts the proposal, and afterwards, Michael announces to the office that he's quitting his job to move to Colorado with Holly.

In a 2021 interview on the Office Ladies podcast, Ryan revealed that she was a fan of the show, and expressed interest to her agent about playing a role.

[1] During the filming of "Goodbye, Toby", Lieberstein commented that "we started to see this really silly side that Amy brought to the character, and [we] found almost like a junior Michael in her.