Michael regrets revealing that Stanley is having an affair, so he spreads a bunch of lies about everyone else to cover his tracks--except that one of the lies that he spread actually turns out to be true.
Michael sabotages--then promotes--Jim's efforts at getting a promotion, while Dwight and Toby try to prove that Darryl has submitted a fraudulent medical claim.
The Office travels to Niagara Falls to celebrate Jim and Pam's wedding under strict orders not to mention Pam's pregnancy. Michael, Dwight, and Andy all want to hook up with guests at the wedding.
Pam is forced to deal with an embarrassing injury for Andy the night before her wedding, while Kevin deals with the loss of his dress shoes on the morning of the ceremony.
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 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.
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.
The entire office is preoccupied about rumors of Dunder Mifflin's bankruptcy. Michael tries to create a distraction by engaging everyone in a murder-mystery game, but Jim wonders if that is a good idea.
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.
Ten years ago, Michael promised a group of third 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 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.
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.
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.
Pam goes into labor and Jim is ready to take her to the hospital, but she refuses to go. Meanwhile, inspired by Pam and Jim's baby, Dwight and Angela try to reach a "business agreement" to have a baby of their own.
After the baby is born, Pam has trouble getting the baby to breastfeed. At the office, Michael takes credit for hooking Jim and Pam up, and tries to do the same thing for Kevin and Erin, making Andy jealous.
It's St. Patrick's Day, and the CEO forces the office to work late because she won't leave. In addition, Michael unsuccessfully tries to suck up to his new boss, and Andy and Erin's first date is delayed because Erin is sick.
Oscar gets everybody in the office to go to Happy Hour so that he can hit on a coworker in shipping. Pam tries to set up Michael with a friend at the bar, but Michael's alter ego, "Date Mike," threatens to spoil the entire evening.
Michael creates problems for Andy on Secretary's Day when he tells Erin that Andy was engaged to Angela, and Kevin is upset after Oscar makes a video comparing Kevin to Cookie Monster.
Michael is hopeful that a potential client is interested in him, but everyone in the office except Pam thinks he's wasting his time. Meanwhile, Dwight recruits Kelly to apply for the Sabre minority management training program.
Michael becomes convinced that Donna is having an affair and puts Dwight on the case, but Pam soon discovers that the suspicions may be true. Meanwhile, Darryl gets revenge on Andy for an earlier incident.
Michael continues to see Donna even after learning she's married and meeting her husband, Dwight and Angela take their baby contract to an arbitrator, and Jim and Pam struggle to stay awake at the office.
Jo comes to the Scranton branch to find the whistle-blower. However, three different people have confessed to Michael, Michael is protecting them, and the person most people think is the culprit is keeping his mouth shut.