Lily and Marshall seem to keep seeing Barney's doppelgänger, their agreed upon sign to try to get pregnant. Robin gets an offer for an anchor position in Chicago and is torn between accepting it or staying in New York with Don.
Ted, while awaiting the inevitable discovery of what emotional baggage his new girlfriend surely carries, discovers the movie he's taken her to see is based on his relationship with Stella—but with him as the bad guy.
Crashing a snobby high-society party allows Ted to show off how pretentiously intellectual he can be, while Marshall and Lily's baby talk and Robin being off with Don leaves Barney worrying for the future of the gang.
A weekend away having to sleep in twin beds makes Marshall and Lily realize they might help their home life. Robin's possible co-habitation with Don makes both Ted and Barney realize they may want her back.
Ted's repulsed by how erotically his mother's fiancé talks about her, and their wedding spurs him to take drastic action. Marshall reveals crazy things he's done and has everyone guess if he was drunk or a kid.
Lily's furious when Ted brings a date to her birthday dinner, and a review of her photo album shows all the girls Ted's brought to events because he thought they were "the one". Meanwhile, Robin desperately tries to take a bad picture of Barney.
The rest of the gang hopes to make Ted realize he's being strung along by a girl named Tiffany, remembering their own similar situations in the process. Meanwhile, Barney's thrilled when he learns she's a pharmaceutical sales rep, the current 'hot girl' occupation.
Marshall and Lily set up Ted with one of Barney's discards from his Super Bowl plea for phone calls as a Valentine's Day date. Meanwhile, Robin's invited to a party by a Don, which she suspects is really a date.
Depressed over their own lousy weeks—Marshall and Lily were outed as toothrush sharers, Ted mistook a student's name for a gag, and a guy won't call Robin for a second date—the rest of the gang cheer Barney on towards a "perfect week": seven girls in seven days with no rejections.
Ted's neighbor Maggie, that he's wanted to date for years, has finally broken up with her boyfriend, putting her back on the market. A letter written to himself when he was 15 reinforces Marshall's shame that he's become a corporate tool.
Facing deportation, Robin decides to become a U.S. citizen, but she can't seem to let go of her Canadian heritage. Ted and Marshall take a road trip to Chicago, but Lily's decision to join up spoils the fun.
When a girl comes home with Ted from MacLaren's, but merely sleeps and leaves, Barney breaks the news that he's been used for a place to crash. Robin and Barney become the latest to suffer through an awkward "couples night" at Marshall and Lily's.
Robin thinks Barney is cheating on her, but learns he's actually getting "Robin 101" classes from Ted. Marshall tries to give away his barrel, Mabel, by leaving it on the sidewalk, but is miffed that no one seems interested.
Ted realizes his blind date is the same girl he had a blind date with seven years prior, and they use the opportunity to try to learn what they do wrong on first dates. Meanwhile, Barney and Marshall discover a Lily look-alike at a strip club—the "third doppelgänger" for a member of the gang they've found so far.moreless