Neustadter grew up in the Atlantic City suburb of Margate, NJ, where he was an avid movie buff, known for gathering groups of friends weekly for movie outings. He found a way to watch even more movies and dig even deeper into film history when he took a job at a video store as a teenager. Neustadter made his own short videos and loved writing short stories, but thought a career as a writer was a long shot. He decided to pursue the production side of filmmaking, so following his graduation from Atlantic High School in 1994, he studied Film at the University of Pennsylvania. The graduate segued right into film work with a job in the development department at Robert De Niro's Tribeca Productions in New York City. A year later, he met future writing partner Michael H. Weber when he was brought into the department as an intern. The pair discovered they had a shared sense of humor and began to brainstorm ideas just for fun. They had already completed their first feature film script when Neustadter, fearing he would never make it in the entertainment business, took off to London for a year of graduate studies at the London School of Economics.When Neustadter returned to the U.S. at age 25, he moved to Los Angeles and worked as an assistant at CBS and Dreamworks while taking on freelance work as a script reader. Reading such uninspiring work boosted his confidence in his own writing, and he reconnected with Weber on an autobiographical story he was anxious to try to turn into a film. In 2005, he and Weber completed what would become their first screenplay sale, "(500) Days of Summer." It was inspired by an ill-fated romance Neustadter had gone through while in London, and its dialogue-driven approach to the romantic comedy genre earned plenty of positive attention as they shopped it to everyone from major film studios to indie film producers, finally getting an offer from Fox Searchlight studios, which had found success with similarly low-budget, hip offerings as "Sideways" (2004) and "Juno" (2007). Though it was several years before Neustadter and Weber's first collaboration hit the screen, buzz over the newcomers led to the sale of half a dozen more screenplays. The first fruit of their labors to be released in theaters was "The Pink Panther 2" (2009), starring Steve Martin. The broad comedy was a commercial success that took a drubbing from critics, but it did prove that screenwriters Neustadter and Weber had the versatility and willingness to deliver both studio moneymakers and personal projects. A few months later, the two were generating positive attention when "(500) Days of Summer" debuted on the festival circuit, and eventually in theaters. Marc Webb directed, and Joseph Gordon-Levitt starred as an aspiring architect who falls for a lovely and equally music-obsessed Zooey Deschanel, who steadfastly insists that she does not believe in true love.Critics and audiences both fell for the fresh, funny, and realistic take on the romantic comedy, with its un-Hollywood ending, non-linear structure, and a more honest depiction of fragile human bonds than romantic comedy blockbusters relying on flashy settings and big payoff premises. The engaging storytelling and sharply observed (and abundant) dialogue had wide appeal, and while their studio partner was thrilled with the box office take of nearly $50 million on a $7 million production, Neustadter and Weber were embraced by their peers and nominated for an Independent Spirit Award, a Satellite Award, and a Best Screenplay Award nomination from the Broadcast Film Critics' Association.With the success of "(500) Days," Neustadter and Weber became official hot properties in Hollywood, and were tapped to develop their own take on twenty-something relationships with their own primetime series, while collaborating on screen adaptations of James Collins' novel, Beginner's Greek and the Tim Tharp coming-of-age novel, The Spectacular Now, which re-teamed them with director Marc Webb. Off-screen, Neustadter finally put his famed broken heart behind him when he became engaged to film production VP Rachelle Levy in late 2009.