Intrigue

The gang explains to Kevin the origins of the "No Boogie-Boarding" sign in front of MacLaren's, which has to do with Hurricane Irene. Meanwhile, Barney negotiates with Marshall about how to get out of wearing the ducky tie.

A question by Kevin about the origins of a "No Boogie-Boarding" sign outside MacLaren's makes the gang reminisce about Hurricane Irene, which hit New York in the summer of 2011 and was the impetus to the incident that prompted the sign to be erected. - Safety-conscious Ted wanted to leave the city before the approaching hurricane. While Barney, Lily, and Robin thought that Ted was overreacting, Marshall, who was between jobs and had just lost his medical insurance until his new job started in two weeks, was suffering from hypochondria and wanted to leave. But telephone calls from various parents, news of the strength of the hurricane as it got closer and closer to New York, and interpersonal relationships between the five at that time made them continually change their individual minds about whether to go or stay. Meanwhile, Barney is at the point of doing anything to get out of wearing the ducky tie and thinks he has a way to convince Marshall to let him off. As Marshall ponders Barney's deal, Kevin adds his therapist two cents.—Huggo

Barney has grown tired of his Ducky Tie and makes up a story in order to hide the fact that he has thrown it away (In the story Barney is an international spy who uses the tie to save the life of a boy hanging by the side of a building, but then the tie is taken away by a bird), but he is foiled when Lily enters the bar holding the tie after having found it in the garbage.

When entering MacLaren's bar, Kevin notices a sign at the entrance which read "Absolutely no boogie boarding" and asks about it. The group tells him what happened to them during Hurricane Irene on Aug 26th, 2011. Ted had planned to have his friends ride out the hurricane in his house out of the city, but Barney convinces them to stay in his city apartment, saying that the storm is nothing to worry about. Lily and Barney eventually get calls from their parents asking if they are all right, and Robin grows jealous because her father has not called her. When she denies that she feels neglected, Barney fake-calls Robin as her dad to prove her jealousy. The news runs a feature on the storm approaching NYC devastating.

When the group do decide to evacuate to Ted's house, Ted tells Barney that he can't come, as Ted found a girl in Barney's hallway (while Ted was talking to his mom on the mobile) whom he said could ride in Barney's place. This alteration causes altercations (Lily does not want to go with Marshall as she finds him suffocating. Robin is angry at Barney for pretending to be her dad on the phone, and the random girl is angry at Lily for calling her a Floozy); everyone fights over who gets to go or stay, until Ted finally says that he is going to go by himself. Marshall turns on the TV just in time to call Ted back to hear Mayor Bloomberg's speech saying that the evacuation time has passed and that everyone must go inside and wait out the storm.

Marshall had no health insurance during that time because of his unemployment. He was seeing death everywhere and refused to go alone anywhere without Lily because he thought he would be attacked by a bear. Marshall had 2 weeks before he would be added to Lily's plan and in that period, Marshall got really weird, like a clingy Edward Alan Poe. Lily had complained that he was not giving her enough alone time and that all she wanted to do is sit in the bath and read a book. That night, Marshall ran Lily a bath and told her to have a little alone time. Lily said she wanted Marshall to stay, and they ended up conceiving their baby boy in Barney's bathroom.

Meanwhile, in the present, Barney offers to let Marshall deliver his final remaining slap in their Slap Bet in return for being allowed to take the Ducky Tie off. Marshall is torn between slapping Barney and forcing him to continue wearing the tie until Kevin points out that since Barney had not complained about the Ducky Tie in weeks, there must be an agenda to Barney's offer.

Kevin hypothesizes that he has to impress someone and deduces that Barney is going to meet Nora's parents, which Barney reveals happens in two days. Lily and Marshall agree that Barney can take off the tie, but he must gain an extra three slaps to his already existing final slap. Barney agrees and Marshall delivers two of the slaps, with two still remaining.

In the end, it is shown that the gang had gone out after the end of the hurricane and played around in the rain, which led to Marshall going boogie-boarding and eventually crashing through MacLaren's front window - hence the sign against boogie-boarding. Robin and Barney decide to share a cab home and they reminisce about the moment after Marshall's accident when they had almost kissed, but Robin's dad had called her. They make fun of what could have happened and end up kissing in the cab.