| Episode cast overview, first billed only: | |||
| Steve Carell | ... | Michael Scott | |
| Rainn Wilson | ... | Dwight Schrute | |
| John Krasinski | ... | Jim Halpert | |
| Jenna Fischer | ... | Pam Beesly | |
| B.J. Novak | ... | Ryan Howard (credit only) | |
| Ed Helms | ... | Andy Bernard | |
| Leslie David Baker | ... | Stanley Hudson | |
| Brian Baumgartner | ... | Kevin Malone | |
| Creed Bratton | ... | Creed Bratton | |
| Kate Flannery | ... | Meredith Palmer | |
| Mindy Kaling | ... | Kelly Kapoor | |
| Angela Kinsey | ... | Angela Martin | |
| Paul Lieberstein | ... | Toby Flenderson | |
| Oscar Nuñez | ... | Oscar Martinez | |
| Phyllis Smith | ... | Phyllis Vance | |
While on lecture tour to other Dunder Mifflin branches, Michael and Pam discover that Jim's ex-girlfriend Karen is pregnant. At the office, Andy falls for a prospective client, and Jim and Dwight try to set up Kelly's birthday party.
We get to see the full frenemies relationship between Jim and Dwight as they plan a party like two quarreling brothers.