Ted and Barney argue about who has "dibs" on a hot girl at the bar while Marshall's closeness with his father and desire to start a family gets him into trouble with Lily.
The gang comes to help Barney's mom move out of her home, so unravel startling revelations about him. Meanwhile, Ted gets upset when Robin oversells him to a blind date.
Goliath National Bank revives its headquarters project but Ted wants no part of it after what happened to him the last time. Barney tries to convince him of giving it a second chance by using all of his best womanizing tactics. Robin's post-breakup depression leads her to drunk-dial Don.
Robin vows to convince the gang she is a "real" New Yorker, despite their teasing to the contrary, since she hails from Canada. When Woody Allen is spotted in a downtown restaurant, Robin and the gang rush to see the quintessential New Yorker.
Ted is confronted by a beautiful girl named Zoey (Jennifer Morrison) who's upset about the landmark to be torn down to make way for the new GNB headquarters he's designing.
Zoey sits in at Ted's class and gets his students on her side of the fight to save the hotel being torn down for the new GNB headquarters. Ted, Marshall and Barney see Robin in a Halloween "parade". Marshall has problems with his assistant Randy and how GNB treats people.
When the gang goes to a black-tie event at the Natural History Museum, Ted gets introduced to Zoey's husband, The Captain. Barney and Robin dare each other to break the laws of the museum by touching all of the exhibits.
The gang learns about Jessica Glitter (Nicole Scherzinger), a friend of Robin's from her pop-star days as Robin Sparkles, thanks to a new tape Barney discovers about a Canadian children's show.
An old college friend (Jorge Garcia) with a mean streak of bad luck celebrates Thanksgiving with Lily, Robin, Marshall, and Barney. Ted, who cooked a surprise feast for the gang, celebrates the occasion instead with Zoey.
When Ted's new friendship with Zoey tests the theory that single men and married women can't be friends, he invites her husband, "The Captain," to hang out with them. Meanwhile, Marshall and Robin decide to spend alone time together, and Barney and Lily possibly have a fight.
After hearing startling news of Lily being pregnant, everyone must reflect on their lives. Robin becomes newly employed and Ted must do a few things because he is Punchy's best man. Meanwhile, Barney tries to get into the Christmas spirit.
Marshall and Lily see a reproduction specialist out of fear she will never get pregnant while Marshall's parents pay him a surprise visit. Their quest results in both good and bad news. Robin is made a laughing stock at her new job.
The gang consoles Marshall as they all return to Minnesota upon learning of his bad news. Marshall's experiences inspire everyone, causing Barney to muster the courage to find his father.
Barney opens up about himself and his father to Zoey's cousin, Honey (Katy Perry). Ted, whom Zoey had tried to pair up with Honey, confesses to the group his feelings for Zoey.
The gang tries to finalize their plans for Valentine's Day with less than 24 hours to go. Lily faces the prospect of spending the day without Marshall. Robin spends the holiday with her co-workers while Barney tries to take advantage of dateless women.
Barney realizes he has heartfelt attraction for Nora (Nazanin Boniadi) and he thinks that something is wrong with him. Robin dates a guy who acts like a dog.
Barney and his father, Jerome Whittaker (John Lithgow), meet for the first time as father and son. The rest of the gang are struggling with certain issues.
Marshall finally leaves GNB to join an environmental organization – which does not sit well with Barney and Lily. The GNB headquarters project drives another wedge between Ted and Zoey.
In an attempt to bond with his father, Barney asks the gang to embellish their histories with him by adding fake details to their lives. Robin runs into a guy she had a crush on when she and Ted were dating.
Marshall and Barney begin to argue over GNB's demolition of the Arcadian Hotel, and it's up to Robin and Lily to help them make up using cocktails. Ted plans a romantic weekend away for him and Zoey.
Robin and Barney meddle in Ted's relationship but things get more complicated when Barney sees Nora again. An incident makes Marshall think he could get sick with food poisoning. Ted pushes ahead with being best man at a very important wedding. Lily discovers that she is pregnant.
Production
Casting
Jennifer Morrison revelead in an interview that she was contracted for 10 episodes but felt that it was likely she would appear in more.[2]
Co-executive producer Craig Thomas said the issue about the identity of Barney's real father was already a plot point in the initial conceptualization of the series. John Lithgow was the first choice to play Jerome Whittaker and the producers gave him a collection of specific episodes detailing Barney's father issues (including "Showdown") to help him get acquainted with the role. Thomas said Lithgow will still appear in future episodes, as the role would complicate Barney's connection with Nora.[3]