The gang works together to plan a legendary bachelor party for Barney.
When The Captain asks Lily to move to Rome for a year to be his art consultant, she fears that Marshall will resent her. Meanwhile, Ted and Barney become obsessed with a girl who is hiding her amazing body under a puffy coat.
Future versions of Ted and Barney try to convince Ted to go see Robots Versus Wrestlers. Meanwhile, Marshall challenges Robin to a dance-off.
After Robin asks Barney to sell his bachelor pad so they can build a home together, Barney is reluctant and drives away potential buyers. Meanwhile, Lily’s commitment to her job as The Captain’s art consultant strains her relationship with Marshall.
When Ted and Jeanette break up, Barney tries to help him land a new girl by using the infamous playbook Robin thought he had destroyed. Meanwhile, at a gallery opening where Lily hopes to make a good impression, Marshall ends up unintentionally getting noticed.
When Ted receives an unexpected call from The Captain, the gang reminisced about their last awkward encounter with him.
Ted is reluctant to break up with his crazy girlfriend Jeanette. Meanwhile, Robin becomes attached to Marvin after finally holding him for the first time.
Barney uncovers the lost episode of Robin’s “Underneath the Tunes” as Robin Sparkles. Meanwhile, Marshall and Lily are concerned that Ted’s new girlfriend is a stalker.
Barney begs Ted to continue seeing his much younger, much wilder girlfriend, even though Ted has nothing in common with her. Meanwhile, Robin must adjust to the power of the bling.
When Robin learns that Barney never asked her father’s permission before proposing, she insists that he seek his approval before announcing their engagement. Meanwhile, Ted keeps his feelings concealed by throwing himself into planning their wedding.
With Christmas fast approaching, Barney tells Ted that he plans on proposing to Patrice, which leads Ted to debate whether or not to tell Robin. Meanwhile, Marshall and Lily run into an acquaintance from college.
Robin becomes increasingly suspicious of Barney's relationship with Patrice. Meanwhile, Marshall discovers his mother is moving on in her romantic life… with a very disturbing partner.
Robin is determined to get Barney back no matter what it takes. Meanwhile, Ted fills in as Marvin's Nanny, leading Marshall and Lily to realize that Ted is using baby Marvin to replace his other baby…the GNB building.
Marshall takes on his old friend/new nemesis Brad in the biggest case of his career. Meanwhile, the gang reminisces about their own run-ins with the law, leading to a debate over who was the biggest delinquent as a teenager.
Marshall recommends his old law school classmate Brad for a job at his firm, but the interview goes awry, leaving Marshall to do damage control with his boss. Meanwhile, Robin helps negotiate Barney’s return to the strip club circuit.