All I Want is Everything is the third novel in Cecily von Ziegesar's "Gossip Girl series" featuring Blair Waldorf, a Park Avenue socialite.
The novel opens with Blair and her new stepbrother Aaron having been invited to spend their Christmas break from school in St. Barts, where their newly married parents are honeymooning. Blair will be bringing along her best friend Serena, while Aaron will be bringing his friend Miles. One twist in the plot concerns the fact that both stepbrother Aaron and his friend Miles have crushes on Blair.
Another fly in the ointment concerns the fact that Blair is desperately trying to gain admittance to Yale, where her father attended, but her college adviser tells her that the current draft of her entrance essay won't make the cut. Blair almost decides to forgo the trip to St. Barts in favor of spending the break rewriting her essay but can't withstand Serena's persuasion and decides to stick with her travel plans.
Other friends also make it out to St. Barts, including Blair's ex-boyfriend Nate, Nate's new girlfriend Jenny, Jenny's brother Dan, and Dan's girlfriend Vanessa. The long cast of characters weave multiple tales of disappointments in personal accomplishments, disappointments in love, and triumphs in love.
By the time all characters reconvene in New York, Blair having left St. Barts early to work on her essay, breakups have happened and new matches have been formed.