Jessica Day is an offbeat and adorable girl in her late 20s who, after a bad breakup, moves in with three single guys. Goofy, positive, vulnerable and honest to a fault, Jess has faith in people, even when she shouldn't. Although she's dorky and awkward, she's comfortable in her own skin. More prone to friendships with women, she's not used to hanging with the boys--especially at home.
When Cece and Schmidt ask Jess and Nick to be their Maid of Honor and Best Man, respectively, their first task is to plan the engagement party. But when Jess invites Cece’s mom to join in the celebration, Cece is forced to make a surprising announcement to Schmidt.
Jumping back into the dating pool, Jess finds herself dating a dud, but falls in love with his perfect parents. Meanwhile, Nick and Schmidt have very different ideas about how to run the bar.
Jess eagerly reports to jury duty, until she discovers she may be up for a work promotion. Meanwhile, Nick reaches his limit with Cece’s messiness in the loft.
With Jess sequestered at jury duty, Nick turns the loft into an air b-n-b in order to help pay for Schmidt's upcoming bachelor party. Meanwhile, Winston asks Cece for help when he suspects KC is cheating on him.
Schmidt helps Nick ponder his future after Nick’s cousin and his wife visit to ask for a very special handout. Meanwhile, Winston helps Cece shop for a wedding dress.
A beautiful pharmaceutical rep enters the gang’s life when she agrees to sublet Jess’ room while she is on jury duty.
When Nick's attraction to Reagan starts affecting Schmidt and Cece's relationship, they enact a plan to demystify her, in hopes of helping Nick get over her. Meanwhile, Winston teaches Reagan the art of the breakup.
Reagan causes chaos between Nick and Winston when she tells them she’ll sleep with just one of them in an attempt to challenge the guys’ indecisiveness. Meanwhile, Schmidt is reunited with his college frenemy, Benjamin, when looking at wedding venues with Cece.
Things heat up between Nick and Reagan over who can provide the loft with the best air conditioning unit. Meanwhile, Winston uses his “cop voice” to help Schmidt prep Cece for a newscaster audition.
Jess returns from jury duty and attempts to uncover the real identity of a juror sequestered with her. Meanwhile, Reagan prepares to move out of the loft and out of Nick’s life, and Winston and Cece help Schmidt get over his fear of public dancing.
It’s time for Cece to move into the loft. While Jess is helping her friend move out of her beloved apartment, she has to finish the school’s budget by morning, which the new principal has neglected to tell her. Meanwhile, Winston gets a new partner to avoid having to work side-by-side with Aly.
After Cece receives an exciting new job offer, Jess agrees to help Schmidt with the wedding preparations, but things don’t go as planned when Schmidt’s dad, Gavin, appears. Meanwhile, Winston and Nick get into a competition over whose job is harder.
Jess applies for a job at a progressive new school, but things take a turn when she finds out the principal is dating her ex-boyfriend, Sam. Meanwhile, Nick gets a cold and Schmidt quarantines the roommates to prevent himself from getting sick before his big presentation.
When Jess is served a restraining order by her ex-boyfriend, Sam, she sets out to clear her name with Winstons help. Nick and Schmidt plot against the owner of a trendy new bar that opened on their street.
Jess invents a male alter ego, “Jeff Day” in order to buy a new car from a sexist salesman, but her plan backfires when both Nick and Sam arrive at the dealership pretending to be him. Meanwhile, Schmidt and Cece panic when Winston decides to bring his new prankster girlfriend, Rhonda as his plus one to their wedding.
Despite being happy with Sam, Jess confesses to Cece that she had a sex dream about Nick. And Schmidt attempts to help Winston land Furguson a cat audition when he finds out Aly’s boyfriend is a talent agent for pets.
After being emasculated in front of Cece, Schmidt insists on a manly bachelor party weekend in Vegas, but the road trip goes awry when the guys end up at a desert biker bar and he must put his newfound bravado to the test.
Refusing to accept that their crazy days are behind them, Jess and Cece abandon their low-key bachelorette party plans and seek a night out to top all others.
Jess races to make alterations to Cece’s bridal dress, while Schmidt tries to keep his “wedding workshop” a secret at work, and Nick struggles to ask Reagan to be his date to the nuptials. Meanwhile, Winston and Aly try to keep their relationship on the down-low at work.
Jess meets Sam’s female best friend, Diane. Meanwhile, Nick is worried Gavin will disappoint Schmidt again and Winston is offended by a reaction to a birthday gift.
On the night before the wedding, Nick and Winston try to help Schmidt re-write his vows and Jess, thinking that Sam is going to propose to her, rallies the gang into playing True American to avoid giving him an answer.