Ted is still happily dating Karen to the dismay of his friends. This is because everything Karen says is critical and pretentious. One night at the bar, Karen notes Robin is wearing real diamond earrings, which Robin takes as a compliment but Karen criticizes her for exploiting the diamond miners of Sierra Leone. When Karen goes upstairs, Marshall calls her a douche. Ted tells them his friends don't get a say on who he dates, as he calls the shots in his life. As he says this, Karen barks for Ted to join her and he rushes off. The gang talks about why Ted is dating Karen and Lily mentions Karen was Ted's first real girlfriend. Robin realizes it's 2 AM so it's almost time for her to go to work. Lily doesn't think her show can be called a morning show as 4 AM is still the middle of the night. Robin tells her she's used to it and her show's not half bad. The gang answers indiscriminately and Robin realizes they've never watched her show. Robin is hurt and tells them it would mean the world to her if once she knew her friends were out there watching. Marshall tells her on Friday morning everyone will come over to their place at 3 AM in their pajamas and they'll watch her show together. Robin is touched and Lily tells Robin they just want to support her.
Lily's opinion changes when it's 3:30 on Friday morning and she moans she just wants to go to sleep. Marshall mutters he hates Robin for not being more successful and Ted walks in. He tells them Karen dumped him and gives them permission to celebrate. Marshall, Lily and Barney start excitedly jumping up and down. After they're done cheering, Barney asks what happened as he leaves the room. Lily asks what happened and Ted sits down on the couch and laments it was the stupidest thing.
Earlier that night
He and Karen were in his bed playfully throwing pillows at each other when Karen found an earring in Ted's bed. He identified it as one of Robin's earrings and Karen accuses him of sleeping with Robin. She adds she knew this was a mistake and stalks out.
Barney rejoins them in his pajamas and Lily is shocked he sleeps in a pajama-suit. Barney asks what else he would sleep in and Ted suggests a coffin. Marshall remarks it doesn't look comfortable at all and Barney retorts it's not about being comfortable, it's about looking good all the time. Marshall asks why he'd need to look good all the time and Barney tells him about what happened to him a while ago. In the middle of the night, two horny girls covered in massage oil show up at his door and ask to use his shower. Ted tells him that's not a memory, it's from a porn movie. Barney hedges it could happen and he has to be ready if it does. Marshall tells him it's most ridiculous sleeping attire he's ever seen and takes off his robe to reveal a nightgown. Barney is shocked he's wearing a nightgown and starts cracking jokes about it. Marshall calls it a nightshirt and cites it's comfy. Ted adds he lived with Marshall for twelve years, and it's a victory whenever he's wearing clothes at all.
Ted is in Lily and Marshall's room changing into his pajamas when he finds an earring on the dresser, identical to the one Karen found in his bed.
Robin's show is starting when Ted comes in and mutes the TV. He accuses Marshall of planting the earring in his bed and Marshall denies it. Ted starts to yell at him when Lily admits it was her. She broke Ted and Karen up.
On the muted TV, Robin holds up a picture of the gang and waves to the camera as Ted furiously tells Lily off and adds she had no right to break him and Karen up. Lily tells Ted she did it for his own good as he didn't see how awful Karen was and failed the front porch test. Ted asks what the front porch test is as Robin on TV tears up at the thought that her friends are watching. Lily explains that she, Ted and Marshall have been close since college and they mean so much to each other, so when she pictures the future, she pictures them all together.
Old Ted, Marshall and Lily are all retired and playing bridge on the front porch of their beachside house. Although instead of bridge, they appear to be playing any card game and substituting the word bridge. Marshall shouts "Bridge!", throws his cards down and declares he wins.
Barney clarifies Lily has no idea how to play bridge and Lily hedges they're going to take a class and Marshall adds it's important to stay active. Lily goes on that whenever Ted has been dating someone a while, she does the front porch test to see how this person will fit in to their group over the years. It's not a pretty picture when she thinks about Karen there.
Everyone is playing bridge and Karen criticizes them for playing bridge again as opposed to reading a book. Ted points out the dolphins in the ocean to her and she comments the chemical runoff hasn't clogged their blowholes yet. She calls the water a toxic death trap and Marshall and Lily opt for a dip.
Lily summarizes that Karen failed the front porch test and she had to go. Ted can't believe she did that and Lily challenges to think about how awesome he, Lily and Marshall are. Ted thinks about it and agrees they're pretty awesome. As Ted thinks about it, a cook on Robin's show accidentally sets his arm on fire and Robin heroically puts it out. Lily adds whoever sets out to join Team Awesome, the bar is set pretty high. Lily tells him she doesn't think what she did was right and Marshall adds Ted is better off without her. Barney makes another nightgown joke and challenges Marshall to think of five reasons why he would wear it. Marshall points out he doesn't have to wear anything underneath, it's sexy, his grandfather wore one and lived to be 107, no elastic waistband, and when he goes to sleep, it's the most wonderful, free sleep that makes him feel like he's flying. Marshall challenges how Barney feels when he goes to sleep and Barney ashamedly admits he has to lit perfectly still so he doesn't wrinkle his suit-jamas. On the muted TV, the weatherman has a heart attack and Robin rushes out to help him. Lily asks how mad Ted is and he admits if they felt that strongly maybe he's better off without her. Lily agrees she hated doing that again but Karen had to go. Ted catches she said again and presses how many times she's ended his relationship. After some hedging Lily admits she's done this six times. Lily tells him his girlfriend their sophomore year of college was just using Ted but he didn't see it, so when she was taking a nap, Lily snuck into her room and planted a Creed CD on her dresser, which Ted found and was horrified by. Marshall realizes what happened to his Creed CD as Ted asks Lily who else. Lily brings up a weird sci-fi girl he went out with who wanted him to propose when they'd been together two months. Ted barely liked her but was still thinking about it. So when Ted and Marshall were at a sci-fi convention, (Ted dressed as Luke Skywalker, Marshall as Chewbacca) Lily showed up dressed as Darth Vader and used the voice changer to pretend to be his girlfriend and break up with him. Ted is appalled but Lily tells Ted he's a commitment junkie and he falls for these women even if they don't deserve him. On the muted TV, the guest on Robin's show goes into labor. Ted demands what if one of those women was the mother of his children and Lily tells them if there was ever a chance of that, she backed off like with Victoria or Stella. Ted adds or Robin and Lily doesn't answer. Ted demands to know if she broke up him and Robin and she gives an A Few Good Men-esque speech about why she does what she does before admitting she broke up him and Robin. On the muted TV, Robin delivers her guest's baby and Barney emerges from the bathroom wearing a nightshirt, declaring Marshall's grandfather a wise man.
Ted is livid Lily broke him and Robin up and gets another drink. Marshall invites Barney to stand over a heating vent to feel the advantages of the nightshirt. Lily tells Ted she does this because she cares about him and breathless Robin comes in, thrilled that was the show they watched. Barney asks what happened to her and Robin sees the muted TV and realizes they didn't watch her show after all. Ted tells Robin that Lily broke them up and Robin is confused as to what that means and why Marshall and Barney are wearing nightgowns. Ted tells Robin how Lily has taken it upon herself to sabotage many of his relationships, including theirs. Lily protests Robin was different because she didn't want them to break up, but they wanted completely different things out of life and refused to deal with it. Lily could picture that front porch.
Ted, Robin, Lily and Marshall are all on the front porch. Ted is bitter he never had kids because of Robin, and Robin is bitter her career never took off because of Ted. She also wins the game of bridge, taking the fun away from Marshall.
Marshall remarks he doesn't like that scenario at all. Lily tells them she just wanted to them to talk about their issues but unknowingly gave them the words to their breakup. In 2007, she pretends to be reading a magazine article and asks Ted and Robin separately where they see themselves in five years and later that night, they ask each other at dinner. Lily tells Ted he probably wants to be married which is what he tells Robin and she tells Robin she probably wants to be in Tokyo or Paris and Robin tells Ted she probably wants to be in Argentina... or Tokyo or Paris. This is when Ted realized they have an expiration date.
Robin is shocked and Ted tells Lily in the twelve years they'd known each other he'd never been more furious with her. Barney and Marshall go to the bedroom to test-drive their nightshirts and Robin clarifies if it weren't for Lily, she and Ted might still be together. Lily points out they would've stayed together too long, had an awful bitter breakup and not remain friends. Ted tells Lily she got lucky because she met the love of her life in a hallway when she was 18 but that doesn't give her the right to play God to those still trying to find someone. He adds if she is so concerned about who she and Marshall end up on that front porch with, they can have it to themselves.
Barney and Marshall are in bed and Barney is shocked Marshall is this comfy every night and Lily still sleeps with him. Marshall tells him marriage is about unconditional love and Barney settles down in bed and asks Marshall to tell him more about being married. Marshall tells him that when you're worried you've made all the wrong decisions in life, she tells you you're great and it's all going to be okay. Marshall sees Barney has fallen asleep and affectionately says, "Little guy had a big day! We'll talk about it tomorrow. Sweet dreams, slugger." That night when Marshall's flying in his dream, he sees Barney there too and they high-five.
Ted goes into the bar the next night and is surprised to find Karen waiting for him. She tells him Lily explained everything left the note. Ted reads it and Lily apologizes and adds whoever he married will be awesome because they think Ted is and she prepared a gourmet dinner for him and Karen in the apartment. Karen tells him this means they can never see Lily again which isn't a big loss and Ted pictures a whole new front porch.
The only people on the front porch are Ted and Karen. Karen asks if he remembers his college roommate who was married to the shrill idiot girl she hated. Ted smiles and wistfully adds it's been so long and Karen hands him the paper with Marshall's obituary.
In the apartment, Ted tells Robin he realized while it shouldn't matter what his friends think of his girlfriend, it really matters what his girlfriend thinks of his friends. So he ended it with Karen. He adds Lily is a great cook and Robin joins him for the meal Lily prepared. They talk about how good it is and Ted adds no wonder Marshall dies at 68. Robin remarks if it weren't for Lily, they might still be together. Ted agrees and they talk about their relationship the way they didn't two years ago. Ted adds it was good they broke up because they weren't ready but is afraid they won't find anybody else. He asks Robin if they turn forty and they're still single, will she be his back-up wife? Robin accepts his proposal and they talk about conditions, like neither of them can get really fat. Robin only has one; Ted can't wear a nightshirt. Ted promises to never wear a nightshirt.
Barney is asleep in his apartment when there is a knock at the door. He answers the door and finds a girl there. She starts to talk but sees his nightshirt and leaves.