Season 4

65 (1)
Do I Know You?

September 22, 2008

Stella responds yes to Ted's proposal, but Ted realizes he and Stella know very little about each other. After accidentally sending Stella to the hospital (because of her peanut allergy), Ted makes her watch Star Wars to determine if they are compatible. Barney realizes he's in love with Robin. Lily sets him up on a date with Robin, but he continues his womanizing ways.

66 (2)
The Best Burger in New York
September 29, 2008

A "burger-mad" Marshall is on a quest to find the place where he ate the first, and best hamburger he ever had in New York. Marshall accepts a job with Barney's firm. Guest starring Regis Philbin.

67 (3)
I Heart NJ

October 6, 2008

After inviting the gang to Stella's apartment in New Jersey, Ted tries to sell them on the perks of living in the suburbs until he learns that she expects him to move there after they're married. Robin quits her job, stages a mad dash to return to the job, but in the end quits again and takes a new job as a foreign correspondent in Japan.

68 (4)
Intervention

October 13, 2008

While packing and discussing all the damage stories to their apartment, the gang decides they are not ready to take the next steps in their adult lives. But when Ted discovers the gang planned to stage an intervention for his engagement to Stella, he is uncompromising, saying that they should go through with their plans anyway. Robin moves to Japan, and Marshall and Lily pack up to move to their apartment.

69 (5)
Shelter Island

October 20, 2008

After Stella and Ted make the spontaneous decision to get married in three days, the presence of their exes destroys what was to be the "happiest day of their lives." Robin quits her job, returns from Japan, and suggests she may have feelings for Ted, and Stella reunites with her ex-boyfriend and father of her daughter and leaves Ted at the altar. Barney ruins a chance to reunite with Robin.

70 (6)
Happily Ever After
November 3, 2008

The gang goes out for dinner, but Stella's presence nearby prompts each of them to relate a story of a person they'd rather forget. Ted finds the courage to confront Stella, but when he sees how happy she and Lucy are with Tony, he lets go of his anger.

71 (7)
Not a Father's Day
November 10, 2008

Lily and Marshall contemplate having a baby, so Lily turns to Ted and Robin and gets completely different advice on the issue. After Lily becomes extremely drunk and interferes at Marshall's workplace, they decide to put off having a baby. Robin becomes Ted's new roommate. Barney has a pregnancy scare and when it's disproved, he creates a new holiday: Not a Father's Day.

72 (8)
Woooo!

November 17, 2008

Robin is feeling a little lost because of her unemployment, and becomes a "Wooo!" party girl. Lily tries to fit in with Robin's new friends, but Robin confirms that Lily is her best friend and she just needs the Woo! girls to unwind as a single person. Barney gives Ted a shot at designing a new bank building, but Barney is swayed by the Sprockets-like Swedish collective architects "Sven". Marshall steps in and Ted is awarded the contract.

73 (9)
The Naked Man

November 24, 2008

Ted walks in on Robin's date sitting on the couch in the buff. When she later admits she hooked up with him, all the gang try it. Lily angers Marshall when she tries to think of 50 reasons to have sex. Although not a match, Ted starts to forget Stella by dating a new girl and successfully uses the "Naked Man" technique on her.

74 (10)
The Fight

December 8, 2008

Bartender Doug gets Ted and Barney involved in a fight with guys sitting in the gang's favorite booth. They arrive after Doug has knocked out the guys, but take the credit anyway, earning the admiration of everyone except Marshall. But when Ted and Barney are sued by the losers, it's Marshall to the rescue. Lily struggles with two kids in her class who are also fighting.

75 (11)
Little Minnesota
December 15, 2008

Marshall takes Robin to a bar with a Minnesota theme. Ted attempts to keep his visiting sister away from Barney.

76 (12)
Benefits
January 12, 2009

To ease the tension of being roommates, Ted and Robin start to sleep together, enraging Barney. Marshall has trouble finding a restroom to "read a magazine" at his new job. Lily encourages Barney to tell Robin he loves her, and Ted breaks off the "benefits" when he recognizes Barney's feelings. Barney attempts to tell Robin he loves her, but a misunderstanding stops the message from getting through to her.

77 (13)
Three Days of Snow
January 19, 2009

When a blizzard shuts down the city, Marshall and Lily try to continue their longstanding airport reunion tradition while Ted and Barney volunteer to keep MacLaren’s open so they can meet up with some college girls.

78 (14)
The Possimpible
February 2, 2009

Robin has only seven days to get a job or she will be deported back to Canada. After failing at several interviews, Barney produces a video resume for her that eventually gets Robin a talk show job. The others discuss frivolous items on their resumes.

79 (15)
The Stinsons
March 2, 2009

When Barney mysteriously leaves MacLaren's, the gang follow him to a house in Brooklyn, finding that Barney has a wife and child they never knew about. Barney explains that it is all a ruse to please his mother, (Guest Star Frances Conroy) whom they also meet, and that "Betty" and "Tyler" are actors. Betty and Ted are caught in a kiss, which finally forces Barney to confess to his mother. Marshall is upset when Lily admits she hates his mother.

80 (16)
Sorry, Bro
March 9, 2009

When Lily and Marshall hear that Ted's college girlfriend, Karen (Laura Prepon), has moved to New York City, they explain to Barney and Robin how much they dislike her. The episode name was previously known as "Marshall Forgets his Pants" as to Marshall forgetting his pants when going to his work's gym before work.

81 (17)
The Front Porch
March 16, 2009

During a pajama party to watch Robin's early morning talk show, Lily recounts her efforts to sabotage most of Ted's relationships after Ted's girlfriend, Karen (Laura Prepon), finds a woman's earring in his bed. Barney learns the pleasures of nightshirts, and after Karen and Ted break up, Ted and Robin promise to be each others' "back-up spouse".

82 (18)
Old King Clancy
March 23, 2009

When Goliath National Bank cancels plans to build their new headquarters that Ted was hired to design, Barney and Marshall concoct an elaborate lie to keep Ted from knowing he is out of a job. Meanwhile, Robin has a juicy story about a Canadian celebrity.

83 (19)
Murtaugh

March 30, 2009

When Barney hears that Ted has made a list of things he feels the gang is too old to do, he attempts to complete every task on the list within 24 hours to prove Ted wrong. In a counter bet, Ted attempts to do things only old people would do. Marshall and Lily's coaching styles clash when Marshall takes over Lily's kindergarten basketball team.

84 (20)
Mosbius Designs
April 13, 2009

When Ted loses his job and decides to form his own architectural firm out of his apartment, he hires an intern to help get his company off the ground, but the intern gets too close for comfort with some of Ted's friends. Meanwhile, Marshall tries to make himself more valuable at work with a gimmick.

85 (21)
The Three Days Rule
April 27, 2009

When Ted breaks Barney and Marshall's "three days rule" by having a "text" relationship with a girl he just met, they play a cruel joke on him by pretending to be her. Although credited, Lily does not appear in this episode.

86 (22)
Right Place Right Time
May 4, 2009

Barney plans to celebrate his 200th female conquest in style, but ends up with a less than desirable partner. Marshall is obsessed with charts and graphs. A string of seemingly meaningless events causes Ted to run into a former girlfriend--Stella...

87 (23)
As Fast As She Can
May 11, 2009

...and her boyfriend Tony. Feeling he ruined Ted's life, Tony insists on helping him find a job. Ted inadvertently causes a breakup with Stella. However, Ted helps them reunite and finally moves on. As the other relate their tales of outwitting speeding tickets, Barney struggles to do the same. Lily returns after having been gone for several episodes.

88 (24)
The Leap
May 18, 2009

When Ted pulls an all-nighter working on a pitch in an attempt to bring business to his fledgling architecture firm, Marshall tries to lure him to the roof for a surprise 31st birthday party. Barney professes his love for Robin and the story of the Goat is also continued.