As Annie recruits Abed and Troy for a psychology class experiment, Jeff and Shirley bond over their mutual fondness for gossip.
Sam and Dean head to a small town where people are murdered by famous dead icons. However the brothers come to a dead end when two teenagers reveal they saw Paris Hilton kidnap their friend.
Jane, Cho, Rigsby and Van Pelt decide to conduct their own investigation when Lisbon is accused of murdering a child molester she arrested who was recently paroled.
Olivia begins to regain her memories of her encounter with William Bell. Meanwhile, the "First Wave" tries to collect the head of their leader, and the traitor makes his move.
A Nazi claims to have knowledge about the blackouts. Meanwhile, Demetri receives an anonymous tip about the future, and Aaron tries to get approval to have his daughter's body exhumed.
The Dunder Mifflin staff head to Niagara Falls for Jim and Pam's wedding, with the understanding that her pregnancy is a forbidden discussion topic, but Jim's slip of the tongue prods Michael to attempt damage control.
Frank's behavior is more bizarre than usual---so bizarre that even the gang notice---so they decide to stage an intervention.
The designers have to repurpose wedding gowns of newly divorced women into fashionable new looks. They have $25 for a maximum of two yards of additional fabric and one day to complete the challenge.
Lo convinces Reef and Fin to participate in a Tandem surf contest, which she is eager to score a victory to impress her father. When Reef accidentally drops Fin and dislocates her shoulder, Lo forces Broseph to become Reef's partner, with Fin as the coach. Meanwhile, Johnny and Emma pose as a couple in order to film the team Reef and Broseph are up against to see how good they truly are. At the end, Reef makes an attempt at giving Fin flowers. Surprised at the result, Mr. Ridgemount offers to let Lo back in the penthouse. However, Rosie turns up and says that Lo has been running a 'labor camp' at the hotel. Upon hearing this, Mr. Ridgemount changes his mind.
Jules family and friends crash the 10th date with her new boyfriend, Josh. Ellie and Laurie help Jules realize that it's ok to be selfish once in a while, when Jules has a disastrous experience in bed with Josh. Meanwhile, Jules left Travis with Bobby, who has to be responsible and deal with his son.
When two bodies are discovered at the North and South ends of the city, Mac and the team deftly begin to navigate the trail of evidence left behind by the killer.
When Lily Milton is reported missing, her boyfriend, Parker Hubbard, points Detectives Benson and Stabler in the direction of Callum Donovan, Lily's downstairs neighbor and convicted bank robber who spent nineteen years in solitary confinement. During the investigation into Donovan's alibi, Lily is found alive, adding a surprising twist to the case and exposing more of Donovan's dark past.
Will decides to give New Directions some competition between them by having the boys go against the girls. Terri becomes the school nurse to check on Will.
Daria and James fell in love, got engaged and bought a house. Two years later they are still not married and they’re spending over 50% of their income on their home. They need an income suite if they ever hope to tie the knot and keep their heads above water.
Otis is knocked out and wakes believing that he is King Cudenhotep. The only way for him to get back to normal before the farmer comes back is if someone knocks him in the head again, but Otis has beaver guards that prevent others from getting too close to him. When they finally turn Otis back to normal, the farmer see them but get hit on the head believes he is Ben Franklin.
Old Christine finds a suspicious mole on her left breast, and overreacts, thinking shes dying. Meanwhile, Richard tries to negotiate with New Christine regarding their house.
A gang war looms as Silver Sable, Hammerhead and Doctor Octopus vie for a prize that could change the balance of power in New York City's underworld.
Sixty percent of Americans believe in extra terrestrial life forms and one fourth of the general population thinks that aliens have visited the planet. Spurred by this information and a recent influx of reports made by Chilean locals about aliens, Josh and the team embark upon their first ET investigation. Next, a man made international news with his personal footage of an unidentified animal that appeared to be over 40 feet long, floating in Turkish waters. Locals in the city of Van, a far eastern Turkish location, also claimed to have seen the mysterious beast. The story of the Lake Monster has became such a hot topic of discussion that they've built a statue of the monster and formed their own search teams to look for it. Not wanting to miss out on the excitement, Josh and the crew trek 17 hours to join the mission.
Trying to save her job, Frankie organizes a publicity stunt by filling a car with jelly beans. Meanwhile, Sue fails to make the swim team and realizes that she needs glasses and Brick starts reading his mother's romance novels when he can't check books out of the library.