Season four marked the departure of Karen Filippelli as a regular character, although she appeared for a few seconds in the first episode, "Fun Run" and in the sixth episode, "Branch Wars", as the regional manager of the Utica branch. Relationships again emerged as the main theme of the season, with Jim Halpert and Pam Beesley's rising, and Michael Scott and Jan Levinson's, as well as Dwight Schrute and Angela Martin's declining. Technology was another prevalent theme as the office staff struggled with initiatives introduced by Ryan Howard to modernize the company.
Michael comes to believe the office might be cursed in the wake of a freak accident. After scrutinizing each of his staffers' religious beliefs, he organizes a charity 5K "fun run."
Ryan returns to Scranton with a plan to bring Dunder Mifflin into the digital age by launching a new website - Dunder Mifflin Infinity. Michael is worried about ageism and attempts to win back clients using old fashion business skills. Relationships are on the forefront as Ryan returns to an eager Kelly, Jim and Pam are outed to the office, and Angela is still upset with Dwight about her cat.
Michael gleefully anticipates attending the company's Web-site launch party in New York. Meanwhile, Angela arranges a bash in Scranton, while Dwight gets wrapped up in a real paper chase: He tries to sell more paper than the Web site.
Michael is quickly going into debt with Jan renovating his condo. Meanwhile, it's a barn burner when Jim and Pam check in to the Schrute family farm, which has been converted into a bed-and-breakfast.
Michael was excited to know Dunder Mifflin bought television ad space in local markets, including Scranton. Michael wanted to create the perfect commercial. Only problem was Michael wasn't seeing eye to eye with guys who were going to be producing the commercial.
Karen was now the regional manager of the Utica branch and used her position of power to woo Stanley to her branch. For the right price, Stanley agreed to make the transfer. In Scranton the news was welcomed with applause, much to Michael's dismay.
Michael is feeling left out after finding out Ryan took a handful of branch managers and even Toby on a wilderness retreat, but didn't invite him. In order to get back with nature, Michael asks Jim if he would consider a camping trip together. Hypothetically, Jim answered yes.
Michael is driving to New York with Jan where he is going to speak at her deposition. Jan is suing Dunder Mifflin for four million dollars over her wrongful termination. Michael is excited to testify and has memorized every answer Jan told him to.
Michael stages an elaborate plan to finally get Pam and Jim over to his and Jan's place for a dinner party. Jim gets trapped into it and agrees to go. Dwight overhears and wants his invitation, too. Michael says he only has six wine glasses and with Andy and Angela going too, there's not enough room for Dwight.
Pam is becoming more and more annoyed with Michael and his indecisiveness about ordering a desk chair. In Michael's defense, he's become distracted by his crush on the woman who is modeling the chair in the catalogue. He reminds Pam that since the infamous dinner party, he is now a single man.
Ryan returns to Scranton but not to a warm welcome. He is making everyone in the branch come in on a Saturday to re-enter data into the new website. Michael makes it clear that Ryan is the reason they have to come in on the weekend. The rest of the staff aren't happy knowing a computer will be getting credit for all of their sales.
Pam is sporting a new look at work with her glasses. She admits she spent the night at a "friend's" house and forgot her contact solution. Michael makes sure to point out that the glasses make her look ugly, and if she wants to be hot, the glasses need to come off.
Jim is wearing his best golfing uniform because he is hitting the links with a potential client, Phil Maguire. This is a very important account for Jim because he needs to look good to Ryan, who recently put him on probation for his job performance. Andy and Kevin are also joining in the game to show their support.
Toby leaves Dunder Mifflin, and Michael plans a huge goodbye party... out of joy. Angela refuses to help with it, so Michael turns to Phyllis. Dwight and Meredith harass Holly, their new HR representative.