As his 31st birthday nears, an all-nighter to try to get business has Ted realizing he may need to pursue another career than architecture. Meanwhile, Marshall tries to get him up to a rooftop surprise party.

Ted is trying to find a new job, and when an old acquaintance tries to help nothing goes as planned. Barney tries to smooth talk his way out of a ticket.

Ted explains to his future kids how a chance encounter with a former girlfriend changed his life. Barney makes the 200th notch in his bedpost.

When Ted violates the 'three days rule' by continually texting with a girl he's just met, Barney and Marshall retaliate by impersonating her.

Ted goes out on his own as an architect and hires an intern to help get things started, but the intern gets a little too close to others in the gang.

Barney attempts to complete in a single day all the tasks from a list Ted made to prove the gang's not too old to do them.

Marshall and Barney lie to keep Ted from finding out the headquarters he'd been hired to design for GNB has been cancelled.

Ted is shocked to learn that Lily is responsible for many of his breakups with ex-girlfriends—including Karen.

Ted's college girlfriend reenters his life and leaves Marshall and Lily remembering how much they hated her--a fact they never revealed to Ted.

When the gang suspects that Barney has a girlfriend after he mysteriously leaves MacLaren's, they decide to follow him, only to find to their shock that Barney has a wife and child they never knew about.

Robin relies on a video résumé prepared by Barney to land a job before facing deportation back to Canada.

A blizzard hits New York City, threatenting a tradition of Marshall and Lily's and leaving Ted and Barney to keep MacLaren's doors open.

Robin and Ted explore "friends with benefits" while living together. Marshall has trouble with a few reality TV stars.

Marshall takes Robin to a bar with a Minnesota theme. Ted attempts to keep his visiting sister away from Barney.

Ted—to prove he's not a milquetoast—and Barney—to impress Robin—pick a fight with a group of guys sitting in the gang's favorite booth at MacLaren's.

The gang learns a new way to get their dates to sleep with them after Ted walks in on Robin's date sitting naked on the couch.

Robin reconnects with a group of single partiers known as the "Woo Girls". Ted must present Barney a plan for his company's new HQ.

Lily and Marshall are considering having a baby, but Lily wants advice from Ted and Robin, first. However, she soon finds they have very different views.

The gang contemplate ways in which they'd handle an unwanted encounter with a person from their past.

Deciding to wed in three days, Ted and Stella suddenly see their plans shattered by exes.

When Ted is packing his stuff for his move to New Jersey, he discovers that the gang was going to hold an intervention for his engagement to Stella and demands they hold it anyway.

When Stella's babysitter cancels, a night out turns into the gang hanging out at her place, and Ted talks up New Jersey... until he learns Stella wants him to move there after marriage.

Marshall claims that he had the best hamburger in the world during his first week in New York City, but he forgot where the burger joint is located. The gang then hits the streets of Manhattan to help him find it.

Stella has to give Ted an answer. Barney wants to say something to Robin.