Robin shows up with an Argentinean lover, causing Ted to go out for a night on the town with Barney where he hooks up with a tattooed party girl.
On seeing the girls reaction to Robin's new man from Argentina, Gael, Barney and Ted decide to pose as out-of-towners, in order to meet women. Meanwhile, Marshall and Lily prepare "death" folders for each other.
Two beautiful women show that they are both very attracted to Ted and take the party to his place. Here the gang helps Ted realize that bad luck doesn't always come in threes.
When "kid unfriendly" Robin surprisingly forms a bond with the young son of the guy she is dating, she decides it is too serious and must figure out a way to let the little guy down.
When Ted's new girl becomes jealous that the story of how he and his pals met is better than the story of how she and Ted met, her ranking on Barney's "crazy scale" skyrockets.
When a corporate law firm courts Marshall, lawyer Jeff Coatsworth wins him over, forcing him to let go of his dream of saving the earth in favor of the almighty dollar.
When Lily and Marshall decide to buy an apartment, not only do they make every mistake in the book, but Marshall also discovers Lily's dirty little financial secret when they apply for a loan.
When Ted thinks he has met a wonderful girl, the gang can't help but point out a deal-breaking flaw, that eventually leads to a heated exchange of barbs among the group.
As Lily and Marshall host their first Thanksgiving as a married couple, Barney is tortured by the tick-tock of the slap bet countdown clock and the uncertainty of the exact moment Marshall's slap is going to be delivered. Meanwhile, Ted and Robin try to deal with the way their relationship has changed since they broke up.
The gang joins a gym. Meanwhile, Barney encounters his first sexual partner, Rhonda, and she tells him that his brother asked her to sleep with Barney. So Barney, Marshall and Ted head to the Victoria's Secret Fall Fashion Show after-party to prove that he's still got it, but his skills are put to the test when he meets supermodel Heidi Klum.
When the gang finds out that Ted is taking his doctor on a date, they try to convince him, through examples of their own toxic experiences, why it's never a good idea to get into a relationship with someone you see on a regular basis.
When Ted takes a page from Barney's book and lives like there's no tomorrow, he gets a post St. Patty's Day reality check from Marshall.
Continuing his passionate quest to find the woman who will one day be his wife, Ted pursues his beautiful dermatologist, Stella. While Stella turns down his repeated efforts for a date, her office receptionist, Abby, becomes smitten with Ted.
When Barney's love life is sabotaged by a mystery woman, he turns to tournament bracketology to narrow down the field of 64 women with the most cause to hate his guts.
After Marshall is verbally emasculated by his boss, he struggles with the fact that taking a job with a "big bad" corporate law firm may have been a major mistake. Barney introduces his concept of the scream pyramid in which Marshall can take solace by passing down the abuse to soemone beneath his stature, but it ends up falling on deaf ears and he loses his job after snapping back at his boss.
When Robin rekindles things with an old flame from her pop star days, he crushes her again, but Barney, in his own inimitable style, helps her realize that she is awesome and ends up sleeping with her.
In sleeping with Robin, Barney has broken the most important code in his life: The "Bro Code." Barney hires Marshall to find a loophole in the Code to justify his actions but to no avail. In an effort to fix his guilty conscience, he confesses to Ted who already knew from Robin's own confession. Ted informs Barney that he can't continue being friends with him.
When Ted tells the gang that Stella hasn't had sex in five years, he must face the consequences of breaking her trust, just as they are about to take their relationship to that level. Barney, distraught over losing Ted as his wingman, recruits an underling from his office but finds he has his work cut out for him when the guy isn't up to the challenge.
When Barney and Stella's secretary, Abby, realize that they have one thing in common - their mutual hatred of Ted - the "couple" decides to go to the bar to flaunt their new relationship in Ted's face to make him jealous. Barney tried to kick it up a notch by fake proposing to Abby but she fails to notice it's part of the bit.
When Ted is in an accident, he re-evaluates his life and relationship with Stella after he breaks up with her. He realizes he doesn't want to be without her and finally proposes.