Michael suspects Donna is cheating on him and puts P.I. Dwight Schrute on the case. Meanwhile, Andy is frustrated when no one takes his customer's complaint seriously.
Pam and Jim work on their first sales pitch together to Donna, the manager of a local restaurant. But Michael keeps misreading the signals she's putting out. Meanwhile, Dwight encourages Kelly to try out for the minority training program.
Andy pulls out all the stops to give Erin a memorable Secretary's Day. Michael reluctantly takes Erin out to lunch and lets slip about Andy's relationship with Angela. Meanwhile, Oscar circulates a video he created that compares Kevin's voice to Sesame Street's Cookie Monster.
Michael gets kicked out of the bar when he pulls out all the stops to impress a friend of Jim and Pam's. Meanwhile, Andy and Erin do their best to keep their relationship under wraps. Dwight rethinks his pre-natal contract with Angela.
When the sales staff lets Sabre's new "sales is king" policy get to their heads, Michael hides their new, prized leads.
Michael thinks he impressed Jo only to discover someone else in the office caught her eye. Meanwhile, Dwight makes trouble on Jim's first day back from paternity leave. Andy and Erin have an interesting first date.
While Jim and Pam struggle with their newborn child, back at the office Michael decides to set Erin up on a date with Kevin.
Pam’s contractions begin, but she and Jim are determined to wait it out as long as possible so they can have more time at the hospital. Meanwhile the rest of the office tries to distract Pam from the pain with food and entertainment.
Sabre's CEO wants the Scranton branch to have one manager, and Michael voluntarily steps down and lets Jim become the boss when he finds out that salespeople make more money. However, he soon comes to regret the decision.
Michael hates the changes that Dunder Mifflin's new owner is implementing, so he turns to David Wallace for advice. Jim and Pam find the perfect day care center, but Jim's mistake threatens to ruin the interview.
A banker representing a potential buyer comes to the Scranton branch to interview the H.R. department before the sale goes through.
Michael gets upset when Jim promises Phyllis that she can be the office Santa, but the office Christmas party may be overshadowed by some bad news from David Wallace.
10 years ago, Michael promised a group of 3rd graders he would pay for their college tuition if they graduated. Now comes time to pay, and he can't do it. At the office, Dwight's "Employee of the Month" idea gets Jim in big trouble.
Michael speaks out of line at the Dunder Mifflin shareholders meeting and creates a big problem for management, while Jim discovers that nobody in the office thinks he's the "real" boss.
The entire office is preoccupied about rumors of Dunder Mifflin's bankruptcy. Michael tries to create a distraction by engaging everyone in murder-mystery game, but Jim wonders if that is a good idea.
Michael sparks more anger from Pam when he breaks up with her mom on her birthday after he finds out she's 58, and Dwight unsuccessfully tries to get everyone in the office to owe him a favor.
Michael is upset when he becomes the butt of all the office jokes after he falls in a koi pond. Andy and Pam go out together on some cold calls, and everybody mistakes them as a married couple.
Jim and Pam return from their honeymoon and learn, to their horror, that Michael is dating Pam's mom. Meanwhile, Dwight gives Jim a "gift"--which actually has a listening device attached to it.
Michael meets with an insurance salesman that visits the office and is later convinced by Dwight and Andy that he is part of the mafia. Erin accidentally ruins Pam's painting.
Andy suffers an unfortunate accident, while Pam and Jim suffer from pre-wedding jitters.
The Dunder Mifflin staff head to Niagara Falls for Jim and Pam's wedding, with the understanding that her pregnancy is a forbidden discussion topic, but Jim's slip of the tongue prods Michael to attempt damage control.
David Wallace comes bearing the news that not all the staffers will receive a raise this year. Jim pushes Dwight to the limit and causes him to form office alliances. And Pam decides she wants only cash as a wedding gift.
Michael gets worried after a request from Jim, and Pam's busy with wedding planning. Darryl's worker's compensation claim makes Dwight suspicious.
A few interns who stayed at Dunder-Mifflin over the summer end their internship. Michael announces some potentially damaging gossip about an employee to the rest of the office, then starts to spread false rumours about others to cover up what he has unwittingly revealed.
