The 118 is inundated by emergencies prompted by ransomware attacks; Athena relives her traumatic attack as the realtor serial rapist case is brought to trial.

A citywide blackout is worsened by a record-breaking heatwave; Chimney speaks to Hen in confidence regarding the state of Maddie's condition.

Athena tries to protect her family from tragedy while the citywide blackout continues; Eddie finds himself forced to make a future-defining decision.

A homecoming parade turns to disaster when a truck collides with celebrating high school students; Harry grapples with being kidnapped.

A man needs help from the 118 after he over-exerts himself while exercising; a groundskeeper is injured by his chainsaw; Harry's recent behavior affects Athena.

Bobby and the 118 are thrust into a dangerous prison riot after they respond to a call about a fire at the facility.

Ted and Barney reminisce about an old friend's wedding, including Marshall's impromptu toast; Robin thinks about telling Barney her feelings for him.

Marshall gets the job offer of his dreams, but worries that the videos he made in the past will come back to haunt him; Ted can't decide who to take to a ball.

Ted runs into an old girlfriend and tries to make amends for cheating; Marshall and Lily make a bet with Barney that could result in him wearing a goofy tie.

Robin is forced to attend therapy sessions mandated by the court after she assaults a girl who was out to ruin Barney's relationship.

Marshall is surprised by his boss's soft approach in settling with a company; Ted takes his architecture class on a field trip where things don't go as planned.

The gang interferes when Ted tries to go on a date with a girl without researching first; Marshall and Lily come to terms with finding out the sex of the baby.

The gang realizes that their romantic partner reminds them of one of their parents; Barney and Nora's romantic evening is ruined by a string of bad events.

Ted finally meets the girl in the slutty pumpkin costume from the Halloween party; Barney finds out that he is partly Canadian; Lily has pregnancy on her mind.

The gang reminisces about what happened during Hurricane Irene; Barney tries to cut a deal with Marshall and Lily to get out of wearing the ducky tie.

Barney and Robin find themselves in a predicament when they try and hide a secret from their significant others; Marshall, Lily, and Ted go to a concert.

Ted and Barney discuss making a life-changing decision together; Robin tries everything she can to discourage Marshall and Lily from moving to Long Island.

Robin receives some shocking news and decides to hide it from the gang; Marshall decides to hang Christmas decorations on the house in the suburbs.

Marshall visits his father's gravesite to carry on a tailgating tradition; Barney and Ted open a bar called "Puzzles"; Robin fills in for a drunk news anchor.

Lily and Marshall make the official move to the suburbs and realize that Lily's bossy father refuses to move out; the gang decides to go to the strip club.

Marshall and Lily decide to throw a highly anticipated housewarming party, but things start to go awry when Ted nearly comes to blows with Marshall's boss.

For Valentine's Day, Lily and Marshall invite Robin and Kevin on a weekend getaway to Vermont, where Kevin and Robin discuss their relationship.

Ted decides to confess his feelings to Robin after she ends up breaking up with Kevin; Barney is on a mission to find something private of Marshall and Lily's.

Barney tries to persuade Quinn to date him even after learning that she is a stripper; Marshall and Lily introduce Robin to life in the suburbs.

The gang tries to split up Barney and Quinn after they hear about plans of them moving in together; Ted and Robin fight over who gets to sublet the apartment.

Ted, Marshall and Barney embark on another "trilogy time," a tradition in which they get together every three years just to watch the "Star Wars" trilogy.

Barney tries to lure Ted into going out every night; Lily has a naughty dream about someone besides Marshall; Robin finally becomes a famous news anchor.

Marshall comes to the realization that the baby is coming soon, and freaks out; Ted and Robin come to terms with their relationship; Barney goes on a road trip.

While Marshall is in Atlantic City with Barney, Lily starts to go into labor, leaving him desperate to make it back to New York before the baby is born.

On Barney's future wedding day, the gang looks back on the time they encouraged Ted to chase after the one woman that got away and reconnect with her.