Plot

On St-Patrick's Day, Ted follows Barney to a bar to party like there's no tomorrow, while Robin discovers something strange about Marshall and Lily's new apartment.

It's St. Patrick's Day 2008. Like they have every year and like most New Yorkers do, Barney believes that he and the gang are going out partying. But Marshall, Lily, Robin and Ted have instead decided to go to Marshall and Lily's new place and play board games. A dejected Barney goes off to party without them. But Barney later convinces Ted to ditch the others and join him when he tells Ted that he has found hot dates for the two of them. Ted feels guilty about ditching the others. As the evening progresses and as Ted feels guilty about one action after another, the evening just gets better and better for him. Reverse karma seems to be working for Ted, but will the universe ultimately punish him by night's end? Meanwhile, Marshall, Lily and Robin head to the new apartment. Robin notices something strange about the place. When she figures it out, she tells Marshall the problem, he who doesn't have the heart to tell his wife that the place they just bought with their life savings has this major, major flaw.—Huggo

Ted, Marshall and Lily decide to spend Saint Patrick's Day holding a board game night at Marshall and Lily's new apartment, rather than drinking green beer with a green-suited Barney. Barney, although insulted, accepts his fate and leaves alone. Soon after, Barney calls Ted, having procured a cab and two hot dates (Mary (Arielle Vandenberg) & Stephanie (Mieko Hillman)) for the night. He proposes his theory of "No Tomorrow" and that "today" will have no consequences, and finally convinces Ted to join him by promising him one of his dates. Ted agrees since Marshall and Lily are smelling each other's hands and Ted knows it will be a long night with them. Future Ted reveals that the Mother was present at the party that he and Barney attended that night.

Back at board game night, Marshall and Robin discover that Marshall and Lily's new apartment is crooked. Marshall convinces Robin to keep it a secret from Lily, at least for the time being. However, when a painting on the wall suddenly moves, Lily senses something weird. To cover the truth, Marshall concocts a story about the ghost of a Confederate general haunting the apartment. Eventually, the secret comes out and Marshall, Lily and Robin end up inventing a game called "apartment roller luge" as a means of getting over the crooked floor.

Meanwhile, out with Barney, Ted discovers that, for one night only, the universe seems to work in reverse and rewards him for every bad deed he does. He ditched Marshall and Lily and found himself with a hot date, then he and Barney ditched their dates in line outside a club (The club was full of nothing but girls and the bouncer was more than happy to let 2 guys in), and inside they found themselves outnumbered by hotter or equally hot women. He puts two expensive bottles of champagne on someone else's tab (named Garrido), and is presented with free caviar. The biggest reward comes when he gets hit on by a sure thing named Ashlee (Vanessa Minnillo). To test his theory he asks Ashlee if she would have a one-night stand with him and then forget about it entirely the next morning, to which she agrees, thus confirming his theory. Then, Ashlee confides in him that she is married, which fills him with panic and guilt. Barney approves of Ted's actions (Its not cheating if you are not the one who is married, It's not cheating if her name has 2 adjacent vowels in it, Its not cheating if she is from a different area code)but disapproves of his reluctance to proceed. Back with Ashlee, Ted hesitates and then gets punched out by the man whose tab he had used.

Ted wakes up at home the next morning with a black eye and fond memories, telling Marshall that after police arrested the man he got to drink for free for the rest of the night. However Marshall is far from impressed and reminds Ted that he committed Credit Card fraud and kissed a married woman. To further the point, he reveals that Ted had accidentally pocket dialed his phone the whole time. Seventeen voice messages are played and remind Ted of how he abandoned his date at the door, ordered champagne on another person's bar tab and wanted to sleep with a woman with no intention of seeing her again (all while extremely drunk). Ashamed of his behavior, Ted thanks Marshall for confronting him with the hard truth.

Ted tells Marshall that fixing a crooked floor will be very expensive and will take a lot of time. Marshall and Lily won't be moving out anytime soon. Ted returns to the club to retrieve his phone, which he had left behind. He doesn't find it, but he grabs an abandoned yellow umbrella and walks home in the rain. Future Ted reveals that his eventual wife had been at the club that night, but they did not meet and he's glad because he knows that if they had, she would not have liked him.

In the last scene, Barney wakes up next to a dumpster, proclaims, "I'm awesome" and stumbles away.