Jill Davies is an ordinary housewife living in a peculiar, unnamed suburb where all adults sport dental braces and opt for golf carts over traditional cars. She is married to Nick and has two children: a seven-year-old son named Julian and a very young daughter named Madison. The relationships in this community are complex; she finds herself both friends and rivals with Lisa Wetbottom, as they competitively pit Julian against Lisa's son, Bob.
The film begins with Jill and Lisa engaging in conversation while watching their kids play soccer. They touch on the unsettling recent murder of a local yoga instructor, and Lisa takes a moment to praise Madison. In a surprising moment of candor, Jill impulsively suggests that Lisa could take Madison as her own daughter, and Lisa agrees.
However, Jill’s life becomes increasingly chaotic as she struggles with the peculiarities of her family, especially the antics of her eccentric son, Julian, who is not only uncoordinated but also has a habit of urinating on himself. Tensions peak at Nick's birthday gathering when an argument erupts between Jill and Julian. In a bizarre twist, Julian sings "Happy Birthday to You" to his father before taking a dive into the pool, only to resurface transformed into a Golden Retriever! While Nick revels in this new, athletic version of their son, Jill yearns for the original Julian, prompting a rift in their marriage.
In a desperate move, Jill approaches Lisa once more to reclaim her daughter, now affectionately referred to as Paige. A seemingly innocent request turns sour when Lisa, feeling betrayed, refuses to part with Madison. At a soccer event, Lisa pretends to be pregnant, utilizing a soccer ball beneath her dress, and celebrates her faux pregnancy with her friends.
After some encouragement from her pals at a bowling alley, Jill finally confronts Nick, expressing her desire for a divorce and kicking him out. The situation spirals further when Nick discovers Julian left unattended in the backyard while Jill is away. Overwhelmed, he takes Julian away, leaving Jill heartbroken. She begs Lisa for her daughter back, but Lisa’s anger leaves Jill empty-handed.
Haunted and desperate, Jill encounters a bizarre stalker – a delusional woman urging her to leave her house. In a fit of panic, Jill flees town, cutting off her dental braces in a symbolic act of emancipation. She drives back to her childhood home, where she encounters a woman with four children. Driven by desperation, Jill abducts one child and brings her to a diner. There, she learns about her stalker's arrest, who turns out to be connected to the murder of the yoga teacher.
The following day, Jill is faced with heart-wrenching reality as she observes her kidnapped “daughter” participate in soccer practice alongside other children. To her shock, she discovers that Lisa has not only moved her family into Jill's home but also arranged for Nick to work as a pool boy. As Jill witnesses the game happening over graves, she stands up from the bleachers, proclaiming her need to leave. The referee warns her for being “out of bounds,” prompting Jill to sheepishly take her seat once again.
